![](dotnetdiagramimages/OpcLabs_EasyOpcUA_OpcLabs_EasyOpc_UA_OperationModel_EasyUAMonitoredItemArguments.png)
'Declaration
<CLSCompliantAttribute(True)> <ComDefaultInterfaceAttribute(OpcLabs.EasyOpc.UA.OperationModel.ComTypes._EasyUAMonitoredItemArguments)> <ComVisibleAttribute(True)> <GuidAttribute("014F8522-306C-4E1B-9A8C-7E940AB94A3E")> <TypeConverterAttribute(System.ComponentModel.ExpandableObjectConverter)> <ValueControlAttribute("OpcLabs.BaseLib.Forms.Common.ObjectSerializationControl, OpcLabs.BaseLibForms, Version=5.81.455.1, Culture=neutral, PublicKeyToken=6faddca41dacb409", DefaultReadWrite=False, Export=True, PageId=10001)> <SerializableAttribute()> Public Class EasyUAMonitoredItemArguments Inherits UAMonitoredItemArguments Implements LINQPad.ICustomMemberProvider, OpcLabs.BaseLib.ComTypes._Info, OpcLabs.BaseLib.ComTypes._Object2, OpcLabs.BaseLib.OperationModel.ComTypes._OperationArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._EasyUAMonitoredItemArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._UAAttributeArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._UAMonitoredItemArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._UANodeArguments, System.ICloneable, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable
'Usage
Dim instance As EasyUAMonitoredItemArguments
[CLSCompliant(true)] [ComDefaultInterface(OpcLabs.EasyOpc.UA.OperationModel.ComTypes._EasyUAMonitoredItemArguments)] [ComVisible(true)] [Guid("014F8522-306C-4E1B-9A8C-7E940AB94A3E")] [TypeConverter(System.ComponentModel.ExpandableObjectConverter)] [ValueControl("OpcLabs.BaseLib.Forms.Common.ObjectSerializationControl, OpcLabs.BaseLibForms, Version=5.81.455.1, Culture=neutral, PublicKeyToken=6faddca41dacb409", DefaultReadWrite=false, Export=true, PageId=10001)] [Serializable()] public class EasyUAMonitoredItemArguments : UAMonitoredItemArguments, LINQPad.ICustomMemberProvider, OpcLabs.BaseLib.ComTypes._Info, OpcLabs.BaseLib.ComTypes._Object2, OpcLabs.BaseLib.OperationModel.ComTypes._OperationArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._EasyUAMonitoredItemArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._UAAttributeArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._UAMonitoredItemArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._UANodeArguments, System.ICloneable, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable
[CLSCompliant(true)] [ComDefaultInterface(OpcLabs.EasyOpc.UA.OperationModel.ComTypes._EasyUAMonitoredItemArguments)] [ComVisible(true)] [Guid("014F8522-306C-4E1B-9A8C-7E940AB94A3E")] [TypeConverter(System.ComponentModel.ExpandableObjectConverter)] [ValueControl("OpcLabs.BaseLib.Forms.Common.ObjectSerializationControl, OpcLabs.BaseLibForms, Version=5.81.455.1, Culture=neutral, PublicKeyToken=6faddca41dacb409", DefaultReadWrite=false, Export=true, PageId=10001)] [Serializable()] public ref class EasyUAMonitoredItemArguments : public UAMonitoredItemArguments, LINQPad.ICustomMemberProvider, OpcLabs.BaseLib.ComTypes._Info, OpcLabs.BaseLib.ComTypes._Object2, OpcLabs.BaseLib.OperationModel.ComTypes._OperationArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._EasyUAMonitoredItemArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._UAAttributeArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._UAMonitoredItemArguments, OpcLabs.EasyOpc.UA.OperationModel.ComTypes._UANodeArguments, System.ICloneable, System.Runtime.Serialization.ISerializable, System.Xml.Serialization.IXmlSerializable
Subscription is initiated by calling one of the SubscribeMonitoredItem, SubscribeDataChange, or SubscribeMultipleMonitoredItems method. For any significant change in the subscribed item, your application will receive the DataChangeNotification event notification, described further below. Obviously, you first need to hook up event handler for that event, and in order to prevent event loss, you should do it before subscribing. Alternatively, you can pass a callback method into the SubscribeMonitoredItem, SubscribeDataChange or SubscribeMultipleMonitoredItems call.
Some items may be changing quite frequently, and receiving all changes that are generated is not desirable for performance reasons; there are also physical limitations to the event throughput in the system. You may also want to influence the amount of received information, or control how and how often the information is delivered. QuickOPC-UA has two sets of parameters for this: subscription parameters and monitoring parameters.
Subscription parameters (can be fully contained in UASubscriptionParameters object) influence the information delivery. Main subscription parameters are the relative priority, and publishing interval (in milliseconds). The publishing interval defines the cyclic rate that the subscription is requested to return notifications to the client.
Monitoring parameters (can be fully contained in UAMonitoringParameters object) influence which information is delivered to the client. Main monitoring parameters are the data change filter (optional), size of monitored item queue, and sampling interval (in milliseconds; it is the fastest rate at which the monitored items should be accessed and evaluated).
The data change filter, if present, is contained in the UADataChangeFilter object, and defines the conditions under which a data change notification should be reported and, optionally, a deadband for value changes where no notification is generated. The Trigger property selects whether a notification is generated only when the status code associated with the value changes, or either the status code or the value change, or if any of the status code, value, or a source timestamp change. The DeadbandType property determines the type of deadband used, and can either select no deadband, absolute deadband, or percent deadband.
There are implicit conversions available from System.Double and UADataChangeTrigger to UADataChangeFilter. This allows the developer to simply use the absolute deadband, or the trigger selection, in place of any data change filter.
In order to make the settings of various parameters easier, QuickOPC-UA allows you to omit the specification of publishing interval in subscription parameters by leaving it at zero (the default). In this case, the component will calculate the publishing interval by dividing the sampling interval by the so-called automatic publishing factor (EasyUAClient.SharedParameters.EngineParameters.AutomaticPublishingFactor) with a default pre-set by the component. The resulting value is limited by the value of EasyUAClient.SharedParameters.EngineParameters.FastestAutomaticPublishingInterval property. This algorithm should determine a suitable publishing interval in the most common cases.
If you want to subscribe to a specific value in OPC address space, call the SubscribeDataChange or SubscribeMonitoredItem method. These methods have number of overloads, but in its simplest form, only three arguments are necessary: an endpoint descriptor, node ID, and a sampling interval. Other callbacks allow you to specify e.g. the callback method, a user-defined state object, absolute deadband value, or pass in a full set of parameters using EasyUAMonitoredItemArguments object. The SubscribeDataChange and SubscribeMonitoredItem methods return a subscription handle that you can later use to change the subscription parameters, or unsubscribe.
It is common to pass in a State argument of type Object. When the monitored item’s value changes, the State argument is then passed to the DataChangeNotification event handler (or your callback method) in the EasyUADataChangeNotificationEventArgs.Arguments object.
The State argument is typically used to provide some sort of correlation between objects in your application, and the event notifications. For example, if you are programming an HMI application and you want the event handler to update the control that displays the item’s value, you may want to set the State argument to the control object itself. When the event notification arrives, you simply update the control indicated by the State property of EasyUADataChangeNotificationEventArgs.Arguments, without having to look it up by Node Id or so. See Use the state instead of handles to identify subscribed entities.
To subscribe to multiple items simultaneously in an efficient manner, call the SubscribeMultipleMonitoredItems method (instead of multiple SubscribeDataChange or SubscribeMonitoredItem calls in a loop). You receive back an array of subscription handles. You pass in an array of EasyUAMonitoredItemArguments objects (each containing information for a single subscription to be made), to the SubscribeMultipleMonitoredItems method.
If you are only interested in certain kinds of changes in the monitored item, or need to reduce the amount of incoming notifications by specifying a deadband, use OPC UA Data Change Filter.
Note: It is NOT an error to subscribe to the same item twice (or more times), even with precisely same parameters. You will receive separate subscription handles, and with regard to your application, this situation will look no different from subscribing to different items. Internally, however, the subscription made to the OPC server might be optimized (merged together), depending on other parameters and circumstances.
OPC UA has one underlying mechanism for subscriptions, and the mechanism is further differentiated by the arguments used and the types of notifications generated. The general subscription mechanism refers to "monitored items", and in the current OPC UA version, the monitored item can represent two types of subscriptions: a subscription to either data changes, or events. The distinction is made by the type of filter specified with the subscription (in its monitoring parameters): It is either a data change filter, or an event filter. Depending on which type of subscription (filter) the monitored item uses, either data change notifications, or event notifications, are generated by the subscription.
Subscription methods that have "MonitoredItem" in their name are the most general ones. They allow you to create either data change or event subscriptions, depending on the data you pass in.
Subscription methods that have "DataChange" in their name are designed to create data change subscriptions only. Because of this specialization, they can have simplified set of arguments that makes most sense with data change subscriptions. These methods, however, do not do anything new as far as OPC UA subscriptions go: They just call the SubscribeMultipleMonitoredItems method internally, creating the generalized input arguments for it as needed.
Subscription methods that have "Event" in their name are designed to create event subscriptions only. Because of this specialization, they can have simplified set of arguments that makes most sense with event subscriptions. These methods, however, also do not do anything new as far as OPC UA subscriptions go: They just call the SubscribeMultipleMonitoredItems method internally, creating the generalized input arguments for it as needed.
You can use the more specialized methods if they provide the functionality you need, and give shorter code. In some cases, the more advanced functionality might be missing from the specialized methods, and in that case you should use the generalized methods and assemble the input arguments yourself.
The example below logs OPC Unified Architecture data changes into an XML file.
The main program:
// This example shows how to subscribe to changes of multiple monitored items and display the value of the monitored item with // each change. // // Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . // OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp . // Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own // a commercial license in order to use Online Forums, and we reply to every post. using System; using OpcLabs.EasyOpc.UA; using OpcLabs.EasyOpc.UA.OperationModel; namespace UADocExamples._EasyUAClient { partial class SubscribeMultipleMonitoredItems { public static void Main1() { UAEndpointDescriptor endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"; // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) // or "https://opcua.demo-this.com:51212/UA/SampleServer/" // Instantiate the client object and hook events. var client = new EasyUAClient(); client.DataChangeNotification += client_DataChangeNotification_Main1; Console.WriteLine("Subscribing..."); client.SubscribeMultipleMonitoredItems(new[] { new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10845", 1000), new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10853", 1000), new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10855", 1000) }); Console.WriteLine("Processing monitored item changed events for 10 seconds..."); System.Threading.Thread.Sleep(10 * 1000); Console.WriteLine("Unsubscribing..."); client.UnsubscribeAllMonitoredItems(); Console.WriteLine("Waiting for 5 seconds..."); System.Threading.Thread.Sleep(5 * 1000); Console.WriteLine("Finished."); } static void client_DataChangeNotification_Main1(object sender, EasyUADataChangeNotificationEventArgs e) { // Display value. if (e.Succeeded) Console.WriteLine($"{e.Arguments.NodeDescriptor}: {e.AttributeData.Value}"); else Console.WriteLine($"{e.Arguments.NodeDescriptor} *** Failure: {e.ErrorMessageBrief}"); } } }
# This example shows how to subscribe to changes of multiple monitored items and display the value of the monitored item with # each change. # # Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . # OPC client and subscriber examples in PowerShell on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-PowerShell . # Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own # a commercial license in order to use Online Forums, and we reply to every post. #requires -Version 5.1 using namespace OpcLabs.EasyOpc.UA using namespace OpcLabs.EasyOpc.UA.OperationModel # The path below assumes that the current directory is [ProductDir]/Examples-NET/PowerShell/Windows . Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUA.dll" Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUAComponents.dll" [UAEndpointDescriptor]$endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" # or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) # or "https://opcua.demo-this.com:51212/UA/SampleServer/" # Instantiate the client object. $client = New-Object EasyUAClient # Data change notification handler Register-ObjectEvent -InputObject $client -EventName DataChangeNotification -Action { # Display value. if ($EventArgs.Succeeded) { Write-Host "$($EventArgs.Arguments.NodeDescriptor): $($EventArgs.AttributeData.Value)" } else { Write-Host "$($EventArgs.Arguments.NodeDescriptor) *** Failure: $($EventArgs.ErrorMessageBrief)" } } Write-Host "Subscribing..." $handleArray = $client.SubscribeMultipleMonitoredItems(@( (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10845")), 1000)), (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10853")), 1000)), (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10855")), 1000)) )) Write-Host Write-Host "Processing monitored item changed events for 10 seconds..." $stopwatch = [System.Diagnostics.Stopwatch]::StartNew() while ($stopwatch.Elapsed.TotalSeconds -lt 10) { Start-Sleep -Seconds 1 } Write-Host "Unsubscribing..." $client.UnsubscribeAllMonitoredItems() Write-Host "Waiting for 5 seconds..." Start-Sleep -Seconds 5 Write-Host "Finished."
' This example shows how to subscribe to changes of multiple monitored items and display the value of the monitored item with ' each change. ' ' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . ' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBNET . ' Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own ' a commercial license in order to use Online Forums, and we reply to every post. Imports OpcLabs.EasyOpc.UA Imports OpcLabs.EasyOpc.UA.OperationModel Namespace _EasyUAClient Partial Friend Class SubscribeMultipleMonitoredItems Public Shared Sub Main1() ' Define which server we will work with. Dim endpointDescriptor As UAEndpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" ' or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) ' or "https://opcua.demo-this.com:51212/UA/SampleServer/" ' Instantiate the client object and hook events Dim client = New EasyUAClient() AddHandler client.DataChangeNotification, AddressOf client_DataChangeNotification Console.WriteLine("Subscribing...") client.SubscribeMultipleMonitoredItems(New EasyUAMonitoredItemArguments() _ { New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10845", 1000), New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10853", 1000), New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10855", 1000) } ) Console.WriteLine("Processing monitored item changed events for 10 seconds...") Threading.Thread.Sleep(10 * 1000) Console.WriteLine("Unsubscribing...") client.UnsubscribeAllMonitoredItems() Console.WriteLine("Waiting for 5 seconds...") Threading.Thread.Sleep(5 * 1000) End Sub Private Shared Sub client_DataChangeNotification(ByVal sender As Object, ByVal e As EasyUADataChangeNotificationEventArgs) ' Display value If e.Succeeded Then Console.WriteLine($"{e.Arguments.NodeDescriptor}: {e.AttributeData.Value}") Else Console.WriteLine($"{e.Arguments.NodeDescriptor} *** Failure: {e.ErrorMessageBrief}") End If End Sub End Class End Namespace
# This example shows how to subscribe to changes of multiple monitored items and display the value of the monitored item # with each change. # # Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . # OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-Python . # Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own # a commercial license in order to use Online Forums, and we reply to every post. # The QuickOPC package is needed. Install it using "pip install opclabs_quickopc". import opclabs_quickopc import time # Import .NET namespaces. from OpcLabs.EasyOpc.UA import * from OpcLabs.EasyOpc.UA.OperationModel import * def dataChangeNotification(sender, e): # Display value. if e.Succeeded: print(e.Arguments.NodeDescriptor, ': ', e.AttributeData.Value, sep='') else: print(e.Arguments.NodeDescriptor, ' *** Failure: ', e.ErrorMessageBrief, sep='') endpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer') # or 'http://opcua.demo-this.com:51211/UA/SampleServer' (currently not supported) # or 'https://opcua.demo-this.com:51212/UA/SampleServer/' # Instantiate the client object and hook events. client = EasyUAClient() client.DataChangeNotification += dataChangeNotification print('Subscribing...') client.SubscribeMultipleMonitoredItems([ EasyUAMonitoredItemArguments( None, endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10845'), UAMonitoringParameters(1000)), EasyUAMonitoredItemArguments( None, endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10853'), UAMonitoringParameters(1000)), EasyUAMonitoredItemArguments( None, endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10855'), UAMonitoringParameters(1000)), ]) print('Processing data change events for 10 seconds...') time.sleep(10) print('Unsubscribing...') client.UnsubscribeAllMonitoredItems() print('Waiting for 5 seconds...') time.sleep(5) print('Finished.')
// This example shows how to obtain parameters of certain monitored item subscription. // // Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . // OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp . // Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own // a commercial license in order to use Online Forums, and we reply to every post. using System; using OpcLabs.EasyOpc.UA; using OpcLabs.EasyOpc.UA.OperationModel; namespace UADocExamples._EasyUAClient { class GetMonitoredItemArguments { public static void Main1() { UAEndpointDescriptor endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"; // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) // or "https://opcua.demo-this.com:51212/UA/SampleServer/" // Instantiate the client object and hook events. var client = new EasyUAClient(); client.DataChangeNotification += client_DataChangeNotification; Console.WriteLine("Subscribing..."); int[] handleArray = client.SubscribeMultipleMonitoredItems(new[] { new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10845", 1000), new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10853", 1000), new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10855", 1000) }); Console.WriteLine("Getting monitored item arguments..."); EasyUAMonitoredItemArguments monitoredItemArguments = client.GetMonitoredItemArguments(handleArray[2]); Console.WriteLine($"NodeDescriptor: {monitoredItemArguments.NodeDescriptor}"); Console.WriteLine($"SamplingInterval: {monitoredItemArguments.MonitoringParameters.SamplingInterval}"); Console.WriteLine($"PublishingInterval: {monitoredItemArguments.SubscriptionParameters.PublishingInterval}"); Console.WriteLine("Waiting for 5 seconds..."); System.Threading.Thread.Sleep(5 * 1000); Console.WriteLine("Unsubscribing..."); client.UnsubscribeAllMonitoredItems(); Console.WriteLine("Waiting for 5 seconds..."); System.Threading.Thread.Sleep(5 * 1000); Console.WriteLine("Finished."); } static void client_DataChangeNotification(object sender, EasyUADataChangeNotificationEventArgs e) { // Your code would do the processing here. } // Example output: // //Subscribing... //Getting monitored item arguments... //NodeDescriptor: NodeId="nsu=http://test.org/UA/Data/ ;i=10855" //SamplingInterval: 1000 //PublishingInterval: 0 //Waiting for 5 seconds... //Unsubscribing... //Waiting for 5 seconds... //Finished. } }
# This example shows how to obtain parameters of certain monitored item subscription. # # Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . # OPC client and subscriber examples in PowerShell on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-PowerShell . # Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own # a commercial license in order to use Online Forums, and we reply to every post. #requires -Version 5.1 using namespace OpcLabs.EasyOpc.UA using namespace OpcLabs.EasyOpc.UA.OperationModel # The path below assumes that the current directory is [ProductDir]/Examples-NET/PowerShell/Windows . Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUA.dll" Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUAComponents.dll" [UAEndpointDescriptor]$endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" # or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) # or "https://opcua.demo-this.com:51212/UA/SampleServer/" # Instantiate the client object. $client = New-Object EasyUAClient # Data change notification handler Register-ObjectEvent -InputObject $client -EventName DataChangeNotification -Action { # Your code would do the processing here. } Write-Host "Subscribing..." $handleArray = $client.SubscribeMultipleMonitoredItems(@( (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10845")), 1000)), (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10853")), 1000)), (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10855")), 1000)) )) Write-Host "Getting monitored item arguments..." $monitoredItemArguments = $client.GetMonitoredItemArguments($handleArray[2]) Write-Host "NodeDescriptor: $($monitoredItemArguments.NodeDescriptor)" Write-Host "SamplingInterval: $($monitoredItemArguments.MonitoringParameters.SamplingInterval)" Write-Host "PublishingInterval: $($monitoredItemArguments.SubscriptionParameters.PublishingInterval)" Write-Host "Waiting for 5 seconds..." Start-Sleep -Seconds 5 Write-Host "Unsubscribing..." $client.UnsubscribeAllMonitoredItems() Write-Host "Waiting for 5 seconds..." Start-Sleep -Seconds 5 Write-Host "Finished." # Example output: # #Subscribing... #Getting monitored item arguments... #NodeDescriptor: NodeId="nsu=http://test.org/UA/Data/ ;i=10855" #SamplingInterval: 1000 #PublishingInterval: 0 #Waiting for 5 seconds... #Unsubscribing... #Waiting for 5 seconds... #Finished.
' This example shows how to obtain parameters of certain monitored item subscription. ' ' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . ' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBNET . ' Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own ' a commercial license in order to use Online Forums, and we reply to every post. Imports OpcLabs.EasyOpc.UA Imports OpcLabs.EasyOpc.UA.OperationModel Namespace _EasyUAClient Friend Class GetMonitoredItemArguments Public Shared Sub Main1() ' Define which server we will work with. Dim endpointDescriptor As UAEndpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" ' or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) ' or "https://opcua.demo-this.com:51212/UA/SampleServer/" ' Instantiate the client object and hook events Dim client = New EasyUAClient() AddHandler client.DataChangeNotification, AddressOf client_DataChangeNotification Console.WriteLine("Subscribing...") Dim handleArray() As Integer = client.SubscribeMultipleMonitoredItems(New EasyUAMonitoredItemArguments() _ { _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10845", 1000), _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10853", 1000), _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10855", 1000) _ } _ ) Console.WriteLine("Getting monitored item arguments...") Dim monitoredItemArguments As EasyUAMonitoredItemArguments = client.GetMonitoredItemArguments(handleArray(2)) Console.WriteLine("NodeDescriptor: {0}", monitoredItemArguments.NodeDescriptor) Console.WriteLine("SamplingInterval: {0}", monitoredItemArguments.MonitoringParameters.SamplingInterval) Console.WriteLine("PublishingInterval: {0}", monitoredItemArguments.SubscriptionParameters.PublishingInterval) Console.WriteLine("Waiting for 5 seconds...") Threading.Thread.Sleep(5 * 1000) Console.WriteLine("Unsubscribing...") client.UnsubscribeAllMonitoredItems() Console.WriteLine("Waiting for 5 seconds...") Threading.Thread.Sleep(5 * 1000) End Sub Private Shared Sub client_DataChangeNotification(ByVal sender As Object, ByVal e As EasyUADataChangeNotificationEventArgs) ' Your code would do the processing here End Sub End Class End Namespace
// This example shows how to obtain parameters of certain monitored item subscription. // // Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . // OPC client and subscriber examples in Object Pascal (Delphi) on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-OP . // Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own // a commercial license in order to use Online Forums, and we reply to every post. type TClientEventHandlers115 = class procedure Client_DataChangeNotification( ASender: TObject; sender: OleVariant; const eventArgs: _EasyUADataChangeNotificationEventArgs); end; procedure TClientEventHandlers115.Client_DataChangeNotification( ASender: TObject; sender: OleVariant; const eventArgs: _EasyUADataChangeNotificationEventArgs); begin // Your code would do the processing here end; class procedure GetMonitoredItemArguments.Main; var Arguments: OleVariant; Client: TEasyUAClient; ClientEventHandlers: TClientEventHandlers115; HandleArray: OleVariant; MonitoredItemArguments1, MonitoredItemArguments2, MonitoredItemArguments3: _EasyUAMonitoredItemArguments; MonitoredItemArguments: _EasyUAMonitoredItemArguments; begin // Instantiate the client object and hook events Client := TEasyUAClient.Create(nil); ClientEventHandlers := TClientEventHandlers115.Create; Client.OnDataChangeNotification := ClientEventHandlers.Client_DataChangeNotification; WriteLn('Subscribing...'); MonitoredItemArguments1 := CoEasyUAMonitoredItemArguments.Create; MonitoredItemArguments1.EndpointDescriptor.UrlString := //'http://opcua.demo-this.com:51211/UA/SampleServer'; //'https://opcua.demo-this.com:51212/UA/SampleServer/'; 'opc.tcp://opcua.demo-this.com:51210/UA/SampleServer'; MonitoredItemArguments1.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10845'; MonitoredItemArguments2 := CoEasyUAMonitoredItemArguments.Create; MonitoredItemArguments2.EndpointDescriptor.UrlString := //'http://opcua.demo-this.com:51211/UA/SampleServer'; //'https://opcua.demo-this.com:51212/UA/SampleServer/'; 'opc.tcp://opcua.demo-this.com:51210/UA/SampleServer'; MonitoredItemArguments2.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10853'; MonitoredItemArguments3 := CoEasyUAMonitoredItemArguments.Create; MonitoredItemArguments3.EndpointDescriptor.UrlString := //'http://opcua.demo-this.com:51211/UA/SampleServer'; //'https://opcua.demo-this.com:51212/UA/SampleServer/'; 'opc.tcp://opcua.demo-this.com:51210/UA/SampleServer'; MonitoredItemArguments3.NodeDescriptor.NodeId.ExpandedText := 'nsu=http://test.org/UA/Data/ ;i=10855'; Arguments := VarArrayCreate([0, 2], varVariant); Arguments[0] := MonitoredItemArguments1; Arguments[1] := MonitoredItemArguments2; Arguments[2] := MonitoredItemArguments3; TVarData(HandleArray).VType := varArray or varVariant; TVarData(HandleArray).VArray := PVarArray( Client.SubscribeMultipleMonitoredItems(Arguments)); WriteLn('Getting monitored item arguments...'); MonitoredItemArguments := Client.GetMonitoredItemArguments(HandleArray[2]); WriteLn('NodeDescriptor: ', MonitoredItemArguments.NodeDescriptor.ToString); WriteLn('SamplingInterval: ', MonitoredItemArguments.MonitoringParameters.ToString); WriteLn('PublishingInterval: ', MonitoredItemArguments.SubscriptionParameters.ToString); WriteLn('Waiting for 5 seconds...'); PumpSleep(5*1000); WriteLn('Unsubscribing...'); Client.UnsubscribeAllMonitoredItems; WriteLn('Waiting for 5 seconds...'); Sleep(5*1000); WriteLn('Finished.'); VarClear(HandleArray); VarClear(Arguments); FreeAndNil(Client); FreeAndNil(ClientEventHandlers); end;
# This example shows how to obtain parameters of certain monitored item subscription. # # Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . # OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-Python . # Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own # a commercial license in order to use Online Forums, and we reply to every post. # The QuickOPC package is needed. Install it using "pip install opclabs_quickopc". import opclabs_quickopc import time # Import .NET namespaces. from OpcLabs.EasyOpc.UA import * from OpcLabs.EasyOpc.UA.OperationModel import * def dataChangeNotification(sender, e): # Your code would do the processing here. pass endpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer') # or 'http://opcua.demo-this.com:51211/UA/SampleServer' (currently not supported) # or 'https://opcua.demo-this.com:51212/UA/SampleServer/' # Instantiate the client object and hook events. client = EasyUAClient() client.DataChangeNotification += dataChangeNotification print('Subscribing...') handleArray = client.SubscribeMultipleMonitoredItems([ EasyUAMonitoredItemArguments( None, UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer'), UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10845'), UAMonitoringParameters(1000)), EasyUAMonitoredItemArguments( None, UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer'), UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10853'), UAMonitoringParameters(1000)), EasyUAMonitoredItemArguments( None, UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer'), UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10855'), UAMonitoringParameters(1000)), ]) print('Getting monitored item arguments...') monitoredItemArguments = client.GetMonitoredItemArguments(handleArray[2]) print('NodeDescriptor: ', monitoredItemArguments.NodeDescriptor, sep='') print('SamplingInterval: ', monitoredItemArguments.MonitoringParameters.SamplingInterval, sep='') print('PublishingInterval: ', monitoredItemArguments.SubscriptionParameters.PublishingInterval, sep='') print('Waiting for 5 seconds...') time.sleep(5) print('Unsubscribing...') client.UnsubscribeAllMonitoredItems() print('Waiting for 5 seconds...') time.sleep(5) print('Finished.')
// This example shows how to obtain dictionary of parameters of all monitored item subscriptions. // // Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . // OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp . // Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own // a commercial license in order to use Online Forums, and we reply to every post. using System; using OpcLabs.EasyOpc.UA; using OpcLabs.EasyOpc.UA.OperationModel; namespace UADocExamples._EasyUAClient { class GetMonitoredItemArgumentsDictionary { public static void Main1() { UAEndpointDescriptor endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"; // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) // or "https://opcua.demo-this.com:51212/UA/SampleServer/" // Instantiate the client object and hook events. var client = new EasyUAClient(); client.DataChangeNotification += client_DataChangeNotification; Console.WriteLine("Subscribing..."); client.SubscribeMultipleMonitoredItems(new[] { new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10845", 1000), new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10853", 1000), new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10855", 1000) }); Console.WriteLine("Getting monitored item arguments dictionary..."); EasyUAMonitoredItemArgumentsDictionary monitoredItemArgumentsDictionary = client.GetMonitoredItemArgumentsDictionary(); foreach (EasyUAMonitoredItemArguments monitoredItemArguments in monitoredItemArgumentsDictionary.Values) { Console.WriteLine(); Console.WriteLine($"NodeDescriptor: {monitoredItemArguments.NodeDescriptor}"); Console.WriteLine($"SamplingInterval: {monitoredItemArguments.MonitoringParameters.SamplingInterval}"); Console.WriteLine($"PublishingInterval: {monitoredItemArguments.SubscriptionParameters.PublishingInterval}"); } Console.WriteLine(); Console.WriteLine("Waiting for 5 seconds..."); System.Threading.Thread.Sleep(5 * 1000); Console.WriteLine("Unsubscribing..."); client.UnsubscribeAllMonitoredItems(); Console.WriteLine("Waiting for 5 seconds..."); System.Threading.Thread.Sleep(5 * 1000); Console.WriteLine("Finished."); } static void client_DataChangeNotification(object sender, EasyUADataChangeNotificationEventArgs e) { // Your code would do the processing here. } // Example output: // //Subscribing... //Getting monitored item arguments dictionary... // //NodeDescriptor: NodeId="nsu=http://test.org/UA/Data/ ;i=10845" //SamplingInterval: 1000 //PublishingInterval: 0 // //NodeDescriptor: NodeId="nsu=http://test.org/UA/Data/ ;i=10853" //SamplingInterval: 1000 //PublishingInterval: 0 // //NodeDescriptor: NodeId="nsu=http://test.org/UA/Data/ ;i=10855" //SamplingInterval: 1000 //PublishingInterval: 0 // //Waiting for 5 seconds... //Unsubscribing... //Waiting for 5 seconds... //Finished. } }
# This example shows how to obtain dictionary of parameters of all monitored item subscriptions. # # Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . # OPC client and subscriber examples in PowerShell on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-PowerShell . # Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own # a commercial license in order to use Online Forums, and we reply to every post. #requires -Version 5.1 using namespace OpcLabs.EasyOpc.UA using namespace OpcLabs.EasyOpc.UA.OperationModel # The path below assumes that the current directory is [ProductDir]/Examples-NET/PowerShell/Windows . Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUA.dll" Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUAComponents.dll" [UAEndpointDescriptor]$endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" # or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) # or "https://opcua.demo-this.com:51212/UA/SampleServer/" # Instantiate the client object. $client = New-Object EasyUAClient # Data change notification handler Register-ObjectEvent -InputObject $client -EventName DataChangeNotification -Action { # Your code would do the processing here. } Write-Host "Subscribing..." $handleArray = $client.SubscribeMultipleMonitoredItems(@( (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10845")), 1000)), (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10853")), 1000)), (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10855")), 1000)) )) Write-Host "Getting monitored item arguments dictionary..." $monitoredItemArgumentsDictionary = $client.GetMonitoredItemArgumentsDictionary() foreach ($monitoredItemArguments in $monitoredItemArgumentsDictionary.Values) { Write-Host Write-Host "NodeDescriptor: $($monitoredItemArguments.NodeDescriptor)" Write-Host "SamplingInterval: $($monitoredItemArguments.MonitoringParameters.SamplingInterval)" Write-Host "PublishingInterval: $($monitoredItemArguments.SubscriptionParameters.PublishingInterval)" } Write-Host Write-Host "Waiting for 5 seconds..." Start-Sleep -Seconds 5 Write-Host "Unsubscribing..." $client.UnsubscribeAllMonitoredItems() Write-Host "Waiting for 5 seconds..." Start-Sleep -Seconds 5 Write-Host "Finished." # Example output: # #Subscribing... #Getting monitored item arguments dictionary... # #NodeDescriptor: NodeId="nsu=http://test.org/UA/Data/ ;i=10845" #SamplingInterval: 1000 #PublishingInterval: 0 # #NodeDescriptor: NodeId="nsu=http://test.org/UA/Data/ ;i=10853" #SamplingInterval: 1000 #PublishingInterval: 0 # #NodeDescriptor: NodeId="nsu=http://test.org/UA/Data/ ;i=10855" #SamplingInterval: 1000 #PublishingInterval: 0 # #Waiting for 5 seconds... #Unsubscribing... #Waiting for 5 seconds... #Finished.
' This example shows how to obtain dictionary of parameters of all monitored item subscriptions. ' ' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . ' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBNET . ' Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own ' a commercial license in order to use Online Forums, and we reply to every post. Imports OpcLabs.EasyOpc.UA Imports OpcLabs.EasyOpc.UA.OperationModel Namespace _EasyUAClient Friend Class GetMonitoredItemArgumentsDictionary Public Shared Sub Main1() ' Define which server we will work with. Dim endpointDescriptor As UAEndpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" ' or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) ' or "https://opcua.demo-this.com:51212/UA/SampleServer/" ' Instantiate the client object and hook events Dim client = New EasyUAClient() AddHandler client.DataChangeNotification, AddressOf client_DataChangeNotification Console.WriteLine("Subscribing...") client.SubscribeMultipleMonitoredItems(New EasyUAMonitoredItemArguments() _ { _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10845", 1000), _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10853", 1000), _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10855", 1000) _ } _ ) Console.WriteLine("Getting monitored item arguments dictionary...") Dim monitoredItemArgumentsDictionary As EasyUAMonitoredItemArgumentsDictionary = _ client.GetMonitoredItemArgumentsDictionary() For Each monitoredItemArguments As EasyUAMonitoredItemArguments In monitoredItemArgumentsDictionary.Values Console.WriteLine() Console.WriteLine("NodeDescriptor: {0}", monitoredItemArguments.NodeDescriptor) Console.WriteLine("SamplingInterval: {0}", monitoredItemArguments.MonitoringParameters.SamplingInterval) Console.WriteLine("PublishingInterval: {0}", monitoredItemArguments.SubscriptionParameters.PublishingInterval) Next monitoredItemArguments Console.WriteLine("Waiting for 5 seconds...") Threading.Thread.Sleep(5 * 1000) Console.WriteLine("Unsubscribing...") client.UnsubscribeAllMonitoredItems() Console.WriteLine("Waiting for 5 seconds...") Threading.Thread.Sleep(5 * 1000) End Sub Private Shared Sub client_DataChangeNotification(ByVal sender As Object, ByVal e As EasyUADataChangeNotificationEventArgs) ' Your code would do the processing here End Sub End Class End Namespace
# This example shows how to obtain dictionary of parameters of all monitored item subscriptions. # # Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . # OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-Python . # Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own # a commercial license in order to use Online Forums, and we reply to every post. # The QuickOPC package is needed. Install it using "pip install opclabs_quickopc". import opclabs_quickopc import time # Import .NET namespaces. from OpcLabs.EasyOpc.UA import * from OpcLabs.EasyOpc.UA.OperationModel import * def dataChangeNotification(sender, e): # Your code would do the processing here. pass endpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer') # or 'http://opcua.demo-this.com:51211/UA/SampleServer' (currently not supported) # or 'https://opcua.demo-this.com:51212/UA/SampleServer/' # Instantiate the client object and hook events. client = EasyUAClient() client.DataChangeNotification += dataChangeNotification print('Subscribing...') handleArray = client.SubscribeMultipleMonitoredItems([ EasyUAMonitoredItemArguments( None, UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer'), UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10845'), UAMonitoringParameters(1000)), EasyUAMonitoredItemArguments( None, UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer'), UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10853'), UAMonitoringParameters(1000)), EasyUAMonitoredItemArguments( None, UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer'), UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10855'), UAMonitoringParameters(1000)), ]) print('Getting monitored item arguments dictionary...') monitoredItemArgumentsDictionary = client.GetMonitoredItemArgumentsDictionary() for monitoredItemArguments in monitoredItemArgumentsDictionary.Values: print() print('NodeDescriptor: ', monitoredItemArguments.NodeDescriptor, sep='') print('SamplingInterval: ', monitoredItemArguments.MonitoringParameters.SamplingInterval, sep='') print('PublishingInterval: ', monitoredItemArguments.SubscriptionParameters.PublishingInterval, sep='') print() print('Waiting for 5 seconds...') time.sleep(5) print('Unsubscribing...') client.UnsubscribeAllMonitoredItems() print('Waiting for 5 seconds...') time.sleep(5) print('Finished.')
// This example shows how to subscribe to changes of multiple monitored items // and display each change, identifying the different subscriptions by an // integer. // // Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . // OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp . // Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own // a commercial license in order to use Online Forums, and we reply to every post. using System; using System.Threading; using OpcLabs.EasyOpc.UA; using OpcLabs.EasyOpc.UA.OperationModel; namespace UADocExamples._EasyUAClient { partial class SubscribeMultipleMonitoredItems { public static void StateAsInteger() { UAEndpointDescriptor endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"; // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) // or "https://opcua.demo-this.com:51212/UA/SampleServer/" // Instantiate the client object and hook events. var client = new EasyUAClient(); client.DataChangeNotification += ClientOnDataChangeNotification_StateAsInteger; Console.WriteLine("Subscribing..."); int[] handleArray = client.SubscribeMultipleMonitoredItems(new[] { new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10845", 1000) {State = 1}, // An integer we have chosen to identify the subscription new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10853", 1000) {State = 2}, // An integer we have chosen to identify the subscription new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10855", 1000) {State = 3} // An integer we have chosen to identify the subscription }); for (int i = 0; i < handleArray.Length; i++) Console.WriteLine($"handleArray[{i}]: {handleArray[i]}"); Console.WriteLine("Processing monitored item changed events for 10 seconds..."); Thread.Sleep(10 * 1000); Console.WriteLine("Unsubscribing..."); client.UnsubscribeAllMonitoredItems(); Console.WriteLine("Waiting for 5 seconds..."); Thread.Sleep(5 * 1000); Console.WriteLine("Finished."); } static void ClientOnDataChangeNotification_StateAsInteger(object sender, EasyUADataChangeNotificationEventArgs eventArgs) { // Obtain the integer state we have passed in. var stateAsInteger = (int) eventArgs.Arguments.State; // Display the data. if (eventArgs.Succeeded) Console.WriteLine($"{stateAsInteger}: {eventArgs.AttributeData}"); else Console.WriteLine($"{stateAsInteger} *** Failure: {eventArgs.ErrorMessageBrief}"); } } }
# This example shows how to subscribe to changes of multiple monitored items # and display each change, identifying the different subscriptions by an # integer. # # Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . # OPC client and subscriber examples in PowerShell on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-PowerShell . # Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own # a commercial license in order to use Online Forums, and we reply to every post. #requires -Version 5.1 using namespace OpcLabs.EasyOpc.UA using namespace OpcLabs.EasyOpc.UA.OperationModel # The path below assumes that the current directory is [ProductDir]/Examples-NET/PowerShell/Windows . Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUA.dll" Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUAComponents.dll" [UAEndpointDescriptor]$endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" # or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) # or "https://opcua.demo-this.com:51212/UA/SampleServer/" # Instantiate the client object. $client = New-Object EasyUAClient # Data change notification handler Register-ObjectEvent -InputObject $client -EventName DataChangeNotification -Action { # Obtain the integer state we have passed in. [int]$stateAsInteger = $EventArgs.Arguments.State # Display the data. if ($EventArgs.Succeeded) { Write-Host "$($stateAsinteger): $($EventArgs.AttributeData)" } else { Write-Host "$($stateAsinteger) *** Failure: $($EventArgs.ErrorMessageBrief)" } } Write-Host "Subscribing..." $handleArray = $client.SubscribeMultipleMonitoredItems(@( (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10845")), 1000) -Property @{State = 1}), # An integer we have chosen to identify the subscription (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10853")), 1000) -Property @{State = 2}), # An integer we have chosen to identify the subscription (New-Object UAMonitoredItemArguments( (New-Object UAAttributeArguments($endpointDescriptor, [UANodeDescriptor]"nsu=http://test.org/UA/Data/ ;i=10855")), 1000) -Property @{State = 3}) # An integer we have chosen to identify the subscription )) for ($i = 0; $i -lt $handleArray.Length; $i++) { Write-Host "handleArray[$($i)]: $($handleArray[$i])" } Write-Host Write-Host "Processing monitored item changed events for 10 seconds..." $stopwatch = [System.Diagnostics.Stopwatch]::StartNew() while ($stopwatch.Elapsed.TotalSeconds -lt 10) { Start-Sleep -Seconds 1 } Write-Host "Unsubscribing..." $client.UnsubscribeAllMonitoredItems() Write-Host "Waiting for 5 seconds..." Start-Sleep -Seconds 5 Write-Host "Finished."
' This example shows how to subscribe to changes of multiple monitored items ' and display each change, identifying the different subscriptions by an ' integer. ' ' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . ' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBNET . ' Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own ' a commercial license in order to use Online Forums, and we reply to every post. Imports OpcLabs.EasyOpc.UA Imports OpcLabs.EasyOpc.UA.OperationModel Namespace _EasyUAClient Partial Friend Class SubscribeMultipleMonitoredItems Public Shared Sub StateAsInteger() ' Define which server we will work with. Dim endpointDescriptor As UAEndpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" ' or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) ' or "https://opcua.demo-this.com:51212/UA/SampleServer/" ' Instantiate the client object and hook events Dim client = New EasyUAClient() AddHandler client.DataChangeNotification, AddressOf ClientOnDataChangeNotification_StateAsInteger Console.WriteLine("Subscribing...") Dim handleArray() As Integer = client.SubscribeMultipleMonitoredItems(New EasyUAMonitoredItemArguments() _ { _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, _ "nsu=http://test.org/UA/Data/ ;i=10845", 1000) _ With {.State = 1}, _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, _ "nsu=http://test.org/UA/Data/ ;i=10853", 1000) _ With {.State = 2}, _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, _ "nsu=http://test.org/UA/Data/ ;i=10855", 1000) _ With {.State = 3} _ } _ ) ' An integer we have chosen to identify the subscription For i As Integer = 0 To handleArray.Length - 1 Console.WriteLine("handleArray[{0}]: {1}", i, handleArray(i)) Next i Console.WriteLine("Processing monitored item changed events for 10 seconds...") Threading.Thread.Sleep(10 * 1000) Console.WriteLine("Unsubscribing...") client.UnsubscribeAllMonitoredItems() Console.WriteLine("Waiting for 5 seconds...") Threading.Thread.Sleep(5 * 1000) Console.WriteLine("Finished.") End Sub Private Shared Sub ClientOnDataChangeNotification_StateAsInteger(ByVal sender As Object, ByVal eventArgs As EasyUADataChangeNotificationEventArgs) ' Obtain the integer state we have passed in. Dim stateAsInteger As Integer = CInt(eventArgs.Arguments.State) ' Display the data If eventArgs.Succeeded Then Console.WriteLine("{0}: {1}", stateAsInteger, eventArgs.AttributeData) Else Console.WriteLine("{0} *** Failure: {1}", stateAsInteger, eventArgs.ErrorMessageBrief) End If End Sub End Class End Namespace
REM This example shows how to subscribe to changes of multiple monitored items REM and display each change, identifying the different subscriptions by an REM integer. REM REM Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . REM OPC client and subscriber examples in Visual Basic on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VB . REM Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own REM a commercial license in order to use Online Forums, and we reply to every post. ' The client object, with events 'Public WithEvents Client6 As EasyUAClient Public Sub SubscribeMultipleMonitoredItems_StateAsInteger_Command_Click() OutputText = "" Set Client6 = New EasyUAClient OutputText = OutputText & "Subscribing..." & vbCrLf Dim MonitoringParameters As New UAMonitoringParameters MonitoringParameters.SamplingInterval = 1000 Dim MonitoredItemArguments1 As New EasyUAMonitoredItemArguments MonitoredItemArguments1.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" MonitoredItemArguments1.nodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10845" Set MonitoredItemArguments1.MonitoringParameters = MonitoringParameters MonitoredItemArguments1.SetState 1 ' An integer we have chosen to identify the subscription Dim MonitoredItemArguments2 As New EasyUAMonitoredItemArguments MonitoredItemArguments2.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" MonitoredItemArguments2.nodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10853" Set MonitoredItemArguments2.MonitoringParameters = MonitoringParameters MonitoredItemArguments2.SetState 2 ' An integer we have chosen to identify the subscription Dim MonitoredItemArguments3 As New EasyUAMonitoredItemArguments MonitoredItemArguments3.endpointDescriptor.UrlString = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" MonitoredItemArguments3.nodeDescriptor.NodeId.expandedText = "nsu=http://test.org/UA/Data/ ;i=10855" Set MonitoredItemArguments3.MonitoringParameters = MonitoringParameters MonitoredItemArguments3.SetState 3 ' An integer we have chosen to identify the subscription Dim arguments(2) As Variant Set arguments(0) = MonitoredItemArguments1 Set arguments(1) = MonitoredItemArguments2 Set arguments(2) = MonitoredItemArguments3 Dim handleArray As Variant handleArray = Client6.SubscribeMultipleMonitoredItems(arguments) Dim i As Long: For i = LBound(handleArray) To UBound(handleArray) OutputText = OutputText & "handleArray(" & i & "): " & handleArray(i) & vbCrLf Next OutputText = OutputText & "Processing monitored item changed events for 10 seconds..." & vbCrLf Pause 10000 OutputText = OutputText & "Unsubscribing..." & vbCrLf Call Client6.UnsubscribeAllMonitoredItems OutputText = OutputText & "Waiting for 5 seconds..." & vbCrLf Pause 5000 Set Client2 = Nothing OutputText = OutputText & "Finished." & vbCrLf End Sub Public Sub Client6_DataChangeNotification(ByVal sender As Variant, ByVal eventArgs As EasyUADataChangeNotificationEventArgs) ' Obtain the integer state we have passed in. Dim stateAsInteger As Integer: stateAsInteger = eventArgs.arguments.State If eventArgs.Succeeded Then OutputText = OutputText & stateAsInteger & ": " & eventArgs.AttributeData & vbCrLf Else OutputText = OutputText & stateAsInteger & " *** Failure: " & eventArgs.ErrorMessageBrief & vbCrLf End If End Sub
# This example shows how to subscribe to changes of multiple monitored items # and display each change, identifying the different subscriptions by an # integer. # # Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . # OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-Python . # Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own # a commercial license in order to use Online Forums, and we reply to every post. # The QuickOPC package is needed. Install it using "pip install opclabs_quickopc". import opclabs_quickopc import time # Import .NET namespaces. from OpcLabs.EasyOpc.UA import * from OpcLabs.EasyOpc.UA.OperationModel import * def dataChangeNotification(sender, eventArgs): # Obtain the integer state we have passed in. stateAsInteger = int(eventArgs.Arguments.State) # Display value. if eventArgs.Succeeded: print(stateAsInteger, ': ', eventArgs.AttributeData.Value, sep='') else: print(stateAsInteger, ' *** Failure: ', eventArgs.ErrorMessageBrief, sep='') endpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer') # or 'http://opcua.demo-this.com:51211/UA/SampleServer' (currently not supported) # or 'https://opcua.demo-this.com:51212/UA/SampleServer/' # Instantiate the client object and hook events. client = EasyUAClient() client.DataChangeNotification += dataChangeNotification print('Subscribing...') monitoredItemArguments1 = EasyUAMonitoredItemArguments( None, endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10845'), UAMonitoringParameters(1000)) monitoredItemArguments1.State = 1 # an integer we have chosen to identify the subscription monitoredItemArguments2 = EasyUAMonitoredItemArguments( None, endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10853'), UAMonitoringParameters(1000)) monitoredItemArguments2.State = 2 # an integer we have chosen to identify the subscription monitoredItemArguments3 = EasyUAMonitoredItemArguments( None, endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10855'), UAMonitoringParameters(1000)) monitoredItemArguments3.State = 3 # an integer we have chosen to identify the subscription client.SubscribeMultipleMonitoredItems([ monitoredItemArguments1, monitoredItemArguments2, monitoredItemArguments3, ]) print('Processing data change events for 10 seconds...') time.sleep(10) print('Unsubscribing...') client.UnsubscribeAllMonitoredItems() print('Waiting for 5 seconds...') time.sleep(5) print('Finished.')
// This example shows how to subscribe to changes of multiple monitored items // and display each change, identifying the different subscriptions by an // object. // // Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . // OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp . // Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own // a commercial license in order to use Online Forums, and we reply to every post. using System; using System.Threading; using OpcLabs.EasyOpc.UA; using OpcLabs.EasyOpc.UA.OperationModel; namespace UADocExamples._EasyUAClient { partial class SubscribeMultipleMonitoredItems { class CustomObject { public CustomObject(string name) { Name = name; } public string Name { get; } } public static void StateAsObject() { UAEndpointDescriptor endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"; // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) // or "https://opcua.demo-this.com:51212/UA/SampleServer/" // Instantiate the client object and hook events var client = new EasyUAClient(); client.DataChangeNotification += ClientOnDataChangeNotification_StateAsObject; Console.WriteLine("Subscribing..."); int[] handleArray = client.SubscribeMultipleMonitoredItems(new[] { new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10845", 1000) {State = new CustomObject("First")}, // A custom object that corresponds to the subscription new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10853", 1000) {State = new CustomObject("Second")}, // A custom object that corresponds to the subscription new EasyUAMonitoredItemArguments(null, endpointDescriptor, "nsu=http://test.org/UA/Data/ ;i=10855", 1000) {State = new CustomObject("Third")}, // A custom object that corresponds to the subscription }); for (int i = 0; i < handleArray.Length; i++) Console.WriteLine($"handleArray[{i}]: {handleArray[i]}"); Console.WriteLine("Processing monitored item changed events for 10 seconds..."); Thread.Sleep(10 * 1000); Console.WriteLine("Unsubscribing..."); client.UnsubscribeAllMonitoredItems(); Console.WriteLine("Waiting for 5 seconds..."); Thread.Sleep(5 * 1000); Console.WriteLine("Finished."); } static void ClientOnDataChangeNotification_StateAsObject(object sender, EasyUADataChangeNotificationEventArgs eventArgs) { // Obtain the custom object we have passed in. var stateAsObject = (CustomObject) eventArgs.Arguments.State; // Display the data if (eventArgs.Succeeded) Console.WriteLine($"{stateAsObject.Name}: {eventArgs.AttributeData}"); else Console.WriteLine($"{stateAsObject.Name} *** Failure: {eventArgs.ErrorMessageBrief}"); } } }
' This example shows how to subscribe to changes of multiple monitored items ' and display each change, identifying the different subscriptions by an ' object. ' ' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . ' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBNET . ' Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own ' a commercial license in order to use Online Forums, and we reply to every post. Imports OpcLabs.EasyOpc.UA Imports OpcLabs.EasyOpc.UA.OperationModel Namespace _EasyUAClient Partial Friend Class SubscribeMultipleMonitoredItems Class CustomObject Public Sub New(ByVal name As String) _Name = name End Sub Public ReadOnly Property Name As String Get Return _Name End Get End Property Private ReadOnly _Name As String End Class Public Shared Sub StateAsObject() ' Define which server we will work with. Dim endpointDescriptor As UAEndpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" ' or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) ' or "https://opcua.demo-this.com:51212/UA/SampleServer/" ' Instantiate the client object and hook events Dim client = New EasyUAClient() AddHandler client.DataChangeNotification, AddressOf ClientOnDataChangeNotification_StateAsObject Console.WriteLine("Subscribing...") Dim handleArray() As Integer = client.SubscribeMultipleMonitoredItems(New EasyUAMonitoredItemArguments() _ { _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, _ "nsu=http://test.org/UA/Data/ ;i=10845", 1000) _ With {.State = New CustomObject("First")}, _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, _ "nsu=http://test.org/UA/Data/ ;i=10853", 1000) _ With {.State = New CustomObject("Second")}, _ New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, _ "nsu=http://test.org/UA/Data/ ;i=10855", 1000) _ With {.State = New CustomObject("Third")} _ } _ ) ' A custom object that corresponds to the subscription For i As Integer = 0 To handleArray.Length - 1 Console.WriteLine("handleArray[{0}]: {1}", i, handleArray(i)) Next i Console.WriteLine("Processing monitored item changed events for 10 seconds...") Threading.Thread.Sleep(10 * 1000) Console.WriteLine("Unsubscribing...") client.UnsubscribeAllMonitoredItems() Console.WriteLine("Waiting for 5 seconds...") Threading.Thread.Sleep(5 * 1000) Console.WriteLine("Finished.") End Sub Private Shared Sub ClientOnDataChangeNotification_StateAsObject(ByVal sender As Object, ByVal eventArgs As EasyUADataChangeNotificationEventArgs) ' Obtain the custom object we have passed in. Dim stateAsObject As CustomObject = CType(eventArgs.Arguments.State, CustomObject) ' Display the data If eventArgs.Succeeded Then Console.WriteLine("{0}: {1}", stateAsObject.Name, eventArgs.AttributeData) Else Console.WriteLine("{0} *** Failure: {1}", stateAsObject.Name, eventArgs.ErrorMessageBrief) End If End Sub End Class End Namespace
# This example shows how to subscribe to changes of multiple monitored items # and display each change, identifying the different subscriptions by an # object. # # Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . # OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-Python . # Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own # a commercial license in order to use Online Forums, and we reply to every post. # The QuickOPC package is needed. Install it using "pip install opclabs_quickopc". import opclabs_quickopc import time # Import .NET namespaces. from OpcLabs.EasyOpc.UA import * from OpcLabs.EasyOpc.UA.OperationModel import * class CustomObject(object): def __init__(self, name): self.name = name def dataChangeNotification(sender, eventArgs): # Obtain the custom object we have passed in. stateAsObject = eventArgs.Arguments.State # Display value. if eventArgs.Succeeded: print(stateAsObject.name, ': ', eventArgs.AttributeData.Value, sep='') else: print(stateAsObject.name, ' *** Failure: ', eventArgs.ErrorMessageBrief, sep='') endpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer') # or 'http://opcua.demo-this.com:51211/UA/SampleServer' (currently not supported) # or 'https://opcua.demo-this.com:51212/UA/SampleServer/' # Instantiate the client object and hook events. client = EasyUAClient() client.DataChangeNotification += dataChangeNotification print('Subscribing...') monitoredItemArguments1 = EasyUAMonitoredItemArguments( None, endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10845'), UAMonitoringParameters(1000)) monitoredItemArguments1.State = CustomObject('First') # a custom object that corresponds to the subscription monitoredItemArguments2 = EasyUAMonitoredItemArguments( None, endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10853'), UAMonitoringParameters(1000)) monitoredItemArguments2.State = CustomObject('Second') # a custom object that corresponds to the subscription monitoredItemArguments3 = EasyUAMonitoredItemArguments( None, endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;i=10855'), UAMonitoringParameters(1000)) monitoredItemArguments3.State = CustomObject('Third') # a custom object that corresponds to the subscription client.SubscribeMultipleMonitoredItems([ monitoredItemArguments1, monitoredItemArguments2, monitoredItemArguments3, ]) print('Processing data change events for 10 seconds...') time.sleep(10) print('Unsubscribing...') client.UnsubscribeAllMonitoredItems() print('Waiting for 5 seconds...') time.sleep(5) print('Finished.')
// This example shows how to subscribe to changes of all data variables under a specified object in OPC UA address space. // // Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . // OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp . // Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own // a commercial license in order to use Online Forums, and we reply to every post. using System; using System.Linq; using OpcLabs.EasyOpc.UA; using OpcLabs.EasyOpc.UA.AddressSpace; using OpcLabs.EasyOpc.UA.OperationModel; namespace UADocExamples._EasyUAClient { partial class SubscribeMultipleMonitoredItems { public static void AllInObject() { UAEndpointDescriptor endpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer"; // or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) // or "https://opcua.demo-this.com:51212/UA/SampleServer/" // Instantiate the client object and hook events var client = new EasyUAClient(); client.DataChangeNotification += client_DataChangeNotification_AllInObject; // Obtain variables under "Scalar" node Console.WriteLine("Browsing..."); UANodeElementCollection nodeElementCollection; try { nodeElementCollection = client.BrowseDataVariables(endpointDescriptor, "nsu=http://test.org/UA/Data/ ;ns=2;i=10787"); } catch (UAException uaException) { Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message); return; } // Create array with monitored item arguments EasyUAMonitoredItemArguments[] monitoredItemArgumentsArray = nodeElementCollection .Select(element => new EasyUAMonitoredItemArguments(null, endpointDescriptor, element)) .ToArray(); Console.WriteLine("Subscribing..."); client.SubscribeMultipleMonitoredItems(monitoredItemArgumentsArray); Console.WriteLine("Processing monitored item changed events for 20 seconds..."); System.Threading.Thread.Sleep(20 * 1000); Console.WriteLine("Unsubscribing..."); client.UnsubscribeAllMonitoredItems(); Console.WriteLine("Waiting for 5 seconds..."); System.Threading.Thread.Sleep(5 * 1000); } static void client_DataChangeNotification_AllInObject(object sender, EasyUADataChangeNotificationEventArgs e) { // Display value if (e.Succeeded) Console.WriteLine("{0}: {1}", e.Arguments.NodeDescriptor, e.AttributeData.Value); else Console.WriteLine("{0} *** Failure: {1}", e.Arguments.NodeDescriptor, e.ErrorMessageBrief); } } }
' This example shows how to subscribe to changes of all data variables under a specified object in OPC UA address space. ' ' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . ' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBNET . ' Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own ' a commercial license in order to use Online Forums, and we reply to every post. Imports System.Linq Imports OpcLabs.EasyOpc.UA Imports OpcLabs.EasyOpc.UA.AddressSpace Imports OpcLabs.EasyOpc.UA.OperationModel Namespace _EasyUAClient Partial Friend Class SubscribeMultipleMonitoredItems Public Shared Sub AllInObject() ' Define which server we will work with. Dim endpointDescriptor As UAEndpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer" ' or "http://opcua.demo-this.com:51211/UA/SampleServer" (currently not supported) ' or "https://opcua.demo-this.com:51212/UA/SampleServer/" ' Instantiate the client object and hook events Dim client = New EasyUAClient() AddHandler client.DataChangeNotification, AddressOf client_DataChangeNotification_AllInObject ' Obtain variables under "Scalar" node Console.WriteLine("Subscribing...") Dim nodeElementCollection As UANodeElementCollection Try nodeElementCollection = client.BrowseDataVariables(endpointDescriptor, "nsu=http://test.org/UA/Data/ ;ns=2;i=10787") Catch uaException As UAException Console.WriteLine("*** Failure: {0}", uaException.GetBaseException.Message) Exit Sub End Try ' Create array with monitored item arguments Dim monitoredItemArgumentsArray() As EasyUAMonitoredItemArguments = nodeElementCollection.Select(Function(element) New EasyUAMonitoredItemArguments(Nothing, endpointDescriptor, element)).ToArray() Console.WriteLine("Subscribing...") client.SubscribeMultipleMonitoredItems(monitoredItemArgumentsArray) Console.WriteLine("Processing monitored item changed events for 20 seconds...") Threading.Thread.Sleep(20 * 1000) Console.WriteLine("Unsubscribing...") client.UnsubscribeAllMonitoredItems() Console.WriteLine("Waiting for 5 seconds...") Threading.Thread.Sleep(5 * 1000) End Sub Private Shared Sub client_DataChangeNotification_AllInObject(ByVal sender As Object, ByVal e As EasyUADataChangeNotificationEventArgs) ' Display value If e.Succeeded Then Console.WriteLine("{0}: {1}", e.Arguments.NodeDescriptor, e.AttributeData.Value) Else Console.WriteLine("{0} *** Failure: {1}", e.Arguments.NodeDescriptor, e.ErrorMessageBrief) End If End Sub End Class End Namespace
# This example shows how to subscribe to changes of multiple monitored items and display the value of the monitored item # with each change. # # Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html . # OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-Python . # Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own # a commercial license in order to use Online Forums, and we reply to every post. # The QuickOPC package is needed. Install it using "pip install opclabs_quickopc". import opclabs_quickopc import time # Import .NET namespaces. from OpcLabs.EasyOpc.UA import * from OpcLabs.EasyOpc.UA.OperationModel import * def dataChangeNotification(sender, e): # Display value. if e.Succeeded: print(e.Arguments.NodeDescriptor, ': ', e.AttributeData.Value, sep='') else: print(e.Arguments.NodeDescriptor, ' *** Failure: ', e.ErrorMessageBrief, sep='') endpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:51210/UA/SampleServer') # or 'http://opcua.demo-this.com:51211/UA/SampleServer' (currently not supported) # or 'https://opcua.demo-this.com:51212/UA/SampleServer/' # Instantiate the client object and hook events. client = EasyUAClient() client.DataChangeNotification += dataChangeNotification # Obtain variables under "Scalar" node. print('Browsing...') try: nodeElementCollection = IEasyUAClientExtension.BrowseDataVariables(client, endpointDescriptor, UANodeDescriptor('nsu=http://test.org/UA/Data/ ;ns=2;i=10787')) except UAException as uaException: print('*** Failure: ' + uaException.GetBaseException().Message) exit() # Create array with monitored item arguments. monitoredItemArgumentsArray = list(map( lambda element: EasyUAMonitoredItemArguments(None, endpointDescriptor, element.ToUANodeDescriptor()), nodeElementCollection)) print('Subscribing...') client.SubscribeMultipleMonitoredItems(monitoredItemArgumentsArray) print('Processing data change events for 20 seconds...') time.sleep(20) print('Unsubscribing...') client.UnsubscribeAllMonitoredItems() print('Waiting for 5 seconds...') time.sleep(5) print('Finished.')
System.Object
OpcLabs.BaseLib.Object2
OpcLabs.BaseLib.Info
OpcLabs.BaseLib.OperationModel.OperationArguments
OpcLabs.EasyOpc.UA.OperationModel.UANodeArguments
OpcLabs.EasyOpc.UA.OperationModel.UAAttributeArguments
OpcLabs.EasyOpc.UA.OperationModel.UAMonitoredItemArguments
OpcLabs.EasyOpc.UA.OperationModel.EasyUAMonitoredItemArguments
OpcLabs.EasyOpc.UA.Generic.EasyUADataChangeArguments<TValue>