'DeclarationEvent MetricNotification As EasySparkplugMetricNotificationEventHandler
'UsageDim instance As IEasySparkplugNotificationEvents Dim handler As EasySparkplugMetricNotificationEventHandler AddHandler instance.MetricNotification, handler
event EasySparkplugMetricNotificationEventHandler MetricNotification
event EasySparkplugMetricNotificationEventHandler^ MetricNotification
The event handler receives an argument of type EasySparkplugMetricNotificationEventArgs containing data related to this event. The following EasySparkplugMetricNotificationEventArgs properties provide information specific to this event.
| Property | Description |
|---|---|
| Arguments | The Sparkplug metric subscription arguments of the subscription that generated this notification. |
| ClientId | The client ID (of the broker connection) associated with this notification. (Inherited from OpcLabs.EasySparkplug.OperationModel.EasySparkplugNotificationEventArgs) |
| ComponentTypes | The Sparkplug component types associated with this notification. (Inherited from OpcLabs.EasySparkplug.OperationModel.EasySparkplugNotificationEventArgs) |
| DeviceId | The Sparkplug device ID associated with this notification. (Inherited from OpcLabs.EasySparkplug.OperationModel.EasySparkplugNotificationEventArgs) |
| Diagnostics | Diagnostics information (such as warnings) assembled during the operation. (Inherited from OpcLabs.BaseLib.OperationModel.OperationEventArgs) |
| DiagnosticsCount | Count of diagnostic information elements assembled during the operation. (Inherited from OpcLabs.BaseLib.OperationModel.OperationEventArgs) |
| DiagnosticsSummary | Textual summary of diagnostics information, one message per line. (Inherited from OpcLabs.BaseLib.OperationModel.OperationEventArgs) |
| EdgeNodeId | The Sparkplug edge node ID associated with this notification. (Inherited from OpcLabs.EasySparkplug.OperationModel.EasySparkplugNotificationEventArgs) |
| ErrorId | Gets or sets the error ID of the error. (Inherited from OpcLabs.BaseLib.OperationModel.OperationEventArgs) |
| ErrorMessage | Gets or sets a message that describes the current exception. (Inherited from OpcLabs.BaseLib.OperationModel.OperationEventArgs) |
| ErrorMessageBrief | The first line of the error message. (Inherited from OpcLabs.BaseLib.OperationModel.OperationEventArgs) |
| Exception | Gets the current exception. Contains null reference when no exception. (Inherited from OpcLabs.BaseLib.OperationModel.OperationEventArgs) |
| GroupId | The Sparkplug group ID associated with this notification. (Inherited from OpcLabs.EasySparkplug.OperationModel.EasySparkplugNotificationEventArgs) |
| HasData | Determines whether this notification delivers data with it. (Inherited from OpcLabs.EasySparkplug.OperationModel.EasySparkplugNotificationEventArgs) |
| IsSynthesized | Indicates whether the notification is synthesized. (Inherited from OpcLabs.EasySparkplug.OperationModel.EasySparkplugNotificationEventArgs) |
| Metadata | The metadata associated with the Sparkplug metric, if available. |
| MetricData | The metric data delivered by this notification, if available. |
| MetricName | The name of the Sparkplug metric. |
| NormalizedDiagnostics | A normalized OpcLabs.BaseLib.OperationModel.OperationEventArgs.Diagnostics collection. (Inherited from OpcLabs.BaseLib.OperationModel.OperationEventArgs) |
| NormalizedException | A normalized OpcLabs.BaseLib.OperationModel.OperationEventArgs.Exception object, or null if there was no error. (Inherited from OpcLabs.BaseLib.OperationModel.OperationEventArgs) |
| NotificationType | The Sparkplug notification type of this notification. (Inherited from OpcLabs.EasySparkplug.OperationModel.EasySparkplugNotificationEventArgs) |
| Succeeded | Gets indication whether the operation has succeeded. (Inherited from OpcLabs.BaseLib.OperationModel.OperationEventArgs) |
| SystemDescriptor | The effective Sparkplug system descriptor of the component that generated the notification. (Inherited from OpcLabs.EasySparkplug.OperationModel.EasySparkplugNotificationEventArgs) |
On the Device (SparkplugDevice), this event is raised when a device command (DCMD) is received from the Host Application. On the Edge Node (EasySparkplugEdgeNodeCore), this event is raised when an edge node command (NCMD) is received from the Host Application, and also for all commands received by the devices that belong to the edge node. You can use the OpcLabs.EasySparkplug.OperationModel.EasySparkplugNotificationEventArgs.ComponentTypes property to distinguish between the device and edge node commands.
On the consumer (EasySparkplugConsumerCore), this event is raised for metrics subscribed through the IEasySparkplugConsumer.SubscribeMetric method (or extension methods that rely on it).
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// This example shows how to subscribe to all metrics of a given edge node and display the name and value of the metric with // each notification. // // In order to publish or observe messages for this example, start the SparkplugEdgeNodeConsoleDemo program first. // // Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html . // Sparkplug examples in C# on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-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.EasySparkplug; using OpcLabs.EasySparkplug.OperationModel; namespace SparkplugDocExamples.Consumer._EasySparkplugConsumer { partial class SubscribeEdgeNodeMetric { public static void Overload1() { // Note that the default port for the "mqtt" scheme is 1883. var hostDescriptor = new SparkplugHostDescriptor("mqtt://localhost"); // Instantiate the consumer object and hook events. var consumer = new EasySparkplugConsumer(); consumer.MetricNotification += consumer_Overload1_MetricNotification; Console.WriteLine("Subscribing..."); // In this example, we specify the precise Sparkplug group ID and edge node ID, but allow any metric name. consumer.SubscribeEdgeNodeMetric(hostDescriptor, "easyGroup", "easySparkplugDemo", "#"); Console.WriteLine("Processing notifications for 20 seconds..."); System.Threading.Thread.Sleep(20 * 1000); Console.WriteLine("Unsubscribing..."); consumer.UnsubscribeAllMetrics(); Console.WriteLine("Waiting for 5 seconds..."); System.Threading.Thread.Sleep(5 * 1000); Console.WriteLine("Finished."); } static void consumer_Overload1_MetricNotification(object sender, EasySparkplugMetricNotificationEventArgs eventArgs) { // Handle different types of notifications. Console.WriteLine(); switch (eventArgs.NotificationType) { case SparkplugNotificationType.Connect: Console.WriteLine($"Connected to Sparkplug host, client ID: {eventArgs.ClientId}."); break; case SparkplugNotificationType.Disconnect: Console.WriteLine("Disconnected from Sparkplug host."); break; case SparkplugNotificationType.Data: Console.WriteLine("Received data from Sparkplug host."); Console.WriteLine($"Metric name: {eventArgs.MetricName}"); Console.WriteLine($"Value: {eventArgs.MetricData?.Value}"); break; case SparkplugNotificationType.Birth: Console.WriteLine("Received birth message from Sparkplug host."); Console.WriteLine($"Metric name: {eventArgs.MetricName}"); Console.WriteLine($"Value: {eventArgs.MetricData?.Value}"); break; case SparkplugNotificationType.Death: Console.WriteLine("Received death message from Sparkplug host."); Console.WriteLine($"Metric name: {eventArgs.MetricName}"); break; } if (!eventArgs.Succeeded) Console.WriteLine($"*** Failure: {eventArgs.ErrorMessageBrief}"); } } }
' This example shows how to subscribe to all metrics of a given edge node and display the name and value of the metric with ' each notification. ' ' In order to publish or observe messages for this example, start the SparkplugEdgeNodeConsoleDemo program first. ' ' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html . ' Sparkplug examples in C# on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-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. Imports OpcLabs.EasySparkplug Imports OpcLabs.EasySparkplug.OperationModel Namespace Global.SparkplugDocExamples.Consumer._EasySparkplugConsumer Partial Class SubscribeEdgeNodeMetric Public Shared Sub Overload1() ' Note that the default port for the "mqtt" scheme is 1883. Dim hostDescriptor = New SparkplugHostDescriptor("mqtt://localhost") ' Instantiate the consumer object and hook events. Dim consumer = New EasySparkplugConsumer() AddHandler consumer.MetricNotification, AddressOf consumer_Overload1_MetricNotification Console.WriteLine("Subscribing...") ' In this example, we specify the precise Sparkplug group ID and edge node ID, but allow any metric name. consumer.SubscribeEdgeNodeMetric(hostDescriptor, "easyGroup", "easySparkplugDemo", "#") Console.WriteLine("Processing notifications for 20 seconds...") Threading.Thread.Sleep(20 * 1000) Console.WriteLine("Unsubscribing...") consumer.UnsubscribeAllMetrics() Console.WriteLine("Waiting for 5 seconds...") Threading.Thread.Sleep(5 * 1000) Console.WriteLine("Finished.") End Sub Private Shared Sub consumer_Overload1_MetricNotification(ByVal sender As Object, ByVal eventArgs As EasySparkplugMetricNotificationEventArgs) ' Handle different types of notifications. Console.WriteLine() Select Case eventArgs.NotificationType Case SparkplugNotificationType.Connect Console.WriteLine($"Connected to Sparkplug host, client ID: {eventArgs.ClientId}.") Case SparkplugNotificationType.Disconnect Console.WriteLine("Disconnected from Sparkplug host.") Case SparkplugNotificationType.Data Console.WriteLine("Received data from Sparkplug host.") Console.WriteLine($"Metric name: {eventArgs.MetricName}") Console.WriteLine($"Value: {eventArgs.MetricData?.Value}") Case SparkplugNotificationType.Birth Console.WriteLine("Received birth message from Sparkplug host.") Console.WriteLine($"Metric name: {eventArgs.MetricName}") Console.WriteLine($"Value: {eventArgs.MetricData?.Value}") Case SparkplugNotificationType.Death Console.WriteLine("Received death message from Sparkplug host.") Console.WriteLine($"Metric name: {eventArgs.MetricName}") End Select If Not eventArgs.Succeeded Then Console.WriteLine($"*** Failure: {eventArgs.ErrorMessageBrief}") End If End Sub End Class End Namespace