QuickOPC User's Guide and Reference
TestSubscriptionAsync Method



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.PubSub.Extensions Namespace > IEasyUASubscriberExtension2 Class : TestSubscriptionAsync Method
The subscriber object that will perform the operation.
Arguments needed to subscribe to a dataset.
A period during which a dataset should be received.
Tests whether an OPC UA PubSub subscription can be successfully established. Asynchronous.
Syntax
'Declaration
 
<ExtensionAttribute()>
<AsyncThrowsAttribute(OpcLabs.EasyOpc.UA.OperationModel.UAException)>
<NotNullAttribute()>
Public Shared Function TestSubscriptionAsync( _
   ByVal subscriber As IEasyUASubscriber, _
   ByVal subscribeDataSetArguments As UASubscribeDataSetArguments, _
   ByVal millisecondsTimeout As Integer _
) As Task(Of UADataSetData)
'Usage
 
Dim subscriber As IEasyUASubscriber
Dim subscribeDataSetArguments As UASubscribeDataSetArguments
Dim millisecondsTimeout As Integer
Dim value As Task(Of UADataSetData)
 
value = IEasyUASubscriberExtension2.TestSubscriptionAsync(subscriber, subscribeDataSetArguments, millisecondsTimeout)
[Extension()]
[AsyncThrows(OpcLabs.EasyOpc.UA.OperationModel.UAException)]
[NotNull()]
public static Task<UADataSetData> TestSubscriptionAsync( 
   IEasyUASubscriber subscriber,
   UASubscribeDataSetArguments subscribeDataSetArguments,
   int millisecondsTimeout
)
[Extension()]
[AsyncThrows(OpcLabs.EasyOpc.UA.OperationModel.UAException)]
[NotNull()]
public:
static Task<UADataSetData^>^ TestSubscriptionAsync( 
   IEasyUASubscriber^ subscriber,
   UASubscribeDataSetArguments^ subscribeDataSetArguments,
   int millisecondsTimeout
) 

Parameters

subscriber
The subscriber object that will perform the operation.
subscribeDataSetArguments
Arguments needed to subscribe to a dataset.
millisecondsTimeout
A period during which a dataset should be received.

Return Value

The method returns a task. The task returns non-null OpcLabs.EasyOpc.UA.PubSub.UADataSetData when the test passes and a dataset has been received, or a null reference if there is no error, but no dataset has been received during the millisecondsTimeout period. The task throws a OpcLabs.EasyOpc.UA.OperationModel.UAException when there is an error establishing the subscription.
Exceptions
ExceptionDescription

A null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

The value of an argument is outside the allowable range of values as defined by the invoked method.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

Remarks

This is an asynchronous method. For a synchronous alternative, see TestSubscription.

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