QuickOPC User's Guide and Reference
Create(String,String,Int32,AESubscriptionFilter,AEAttributeSetDictionary,Boolean,Boolean,Object) Method



OpcLabs.EasyOpcClassic Assembly > OpcLabs.EasyOpc.AlarmsAndEvents.Reactive Namespace > AENotificationObservable Class > Create Method : Create(String,String,Int32,AESubscriptionFilter,AEAttributeSetDictionary,Boolean,Boolean,Object) Method
Name of the machine. Determines the computer on which the OPC server is located. May be an empty string, in which case the OPC server is assumed to exist on the local computer or at the computer specified for it by DCOM configuration.
Contains ProgID of the OPC server.
The requested notification rate. The notification rate is in milliseconds and tells the server how often to send event notifications. This is a minimum time - do not send event notifications any faster that this UNLESS the buffer size is reached. A value of 0 for notification rate means that the server should send event notifications as soon as it gets them. This parameter is used to improve communications efficiency between client and server. This parameter is a recommendation from the client, and the server is allowed to ignore the parameter.
An OpcLabs.EasyOpc.AlarmsAndEvents.AESubscriptionFilter that determines the filtering criteria to be used for the event subscription.
Determines the attributes to be returned for each category with event notifications. A dictionary where they key is the category ID, and the value is an array of attribute IDs for that event category.
Creates activated or deactivated subscription. See ChangeEventSubscription for more information.
When set, the subscription will automatically perform a Refresh after each successful connection to the server (either the initial connection, or any automatic reconnection after the connection is lost).
The state object (can be any value supplied by your code); available in event notifications.
Creates a new notification observable for OPC events given by the machine name, server class, and other parameters.
Syntax
'Declaration
 
<NotNullAttribute()>
Public Overloads Shared Function Create( _
   ByVal machineName As String, _
   ByVal serverClass As String, _
   ByVal notificationRate As Integer, _
   ByVal filter As AESubscriptionFilter, _
   ByVal returnedAttributesByCategory As AEAttributeSetDictionary, _
   Optional ByVal active As Boolean, _
   Optional ByVal refreshWhenActive As Boolean, _
   Optional ByVal state As Object _
) As AENotificationObservable
'Usage
 
Dim machineName As String
Dim serverClass As String
Dim notificationRate As Integer
Dim filter As AESubscriptionFilter
Dim returnedAttributesByCategory As AEAttributeSetDictionary
Dim active As Boolean
Dim refreshWhenActive As Boolean
Dim state As Object
Dim value As AENotificationObservable
 
value = AENotificationObservable.Create(machineName, serverClass, notificationRate, filter, returnedAttributesByCategory, active, refreshWhenActive, state)

Parameters

machineName
Name of the machine. Determines the computer on which the OPC server is located. May be an empty string, in which case the OPC server is assumed to exist on the local computer or at the computer specified for it by DCOM configuration.
serverClass
Contains ProgID of the OPC server.
notificationRate
The requested notification rate. The notification rate is in milliseconds and tells the server how often to send event notifications. This is a minimum time - do not send event notifications any faster that this UNLESS the buffer size is reached. A value of 0 for notification rate means that the server should send event notifications as soon as it gets them. This parameter is used to improve communications efficiency between client and server. This parameter is a recommendation from the client, and the server is allowed to ignore the parameter.
filter
An OpcLabs.EasyOpc.AlarmsAndEvents.AESubscriptionFilter that determines the filtering criteria to be used for the event subscription.
returnedAttributesByCategory
Determines the attributes to be returned for each category with event notifications. A dictionary where they key is the category ID, and the value is an array of attribute IDs for that event category.
active
Creates activated or deactivated subscription. See ChangeEventSubscription for more information.
refreshWhenActive
When set, the subscription will automatically perform a Refresh after each successful connection to the server (either the initial connection, or any automatic reconnection after the connection is lost).
state
The state object (can be any value supplied by your code); available in event notifications.

Return Value

Returns an observable for notifications about given OPC events.
Remarks
The AEReactive.DefaultClientSelector selector will be used for OPC Alarms&Events operations.
Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows

See Also