QuickOPC User's Guide and Reference
TestConnectionAsync(IEasyUASubscriber,UASubscribeDataSetArguments,Int32) Method



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.PubSub.Extensions Namespace > IEasyUASubscriberExtension2 Class > TestConnectionAsync Method : TestConnectionAsync(IEasyUASubscriber,UASubscribeDataSetArguments,Int32) Method
The subscriber object that will perform the operation.
Holds all arguments needed to subscribe to a dataset in OPC UA PubSub.
Number of milliseconds to wait before the connection test can pass.
Tests whether an OPC UA PubSub connection can be successfully established. Asynchronous.
Syntax
'Declaration
 
<ExtensionAttribute()>
<AsyncThrowsAttribute(OpcLabs.EasyOpc.UA.OperationModel.UAException)>
<NotNullAttribute()>
Public Overloads Shared Function TestConnectionAsync( _
   ByVal subscriber As IEasyUASubscriber, _
   ByVal subscribeDataSetArguments As UASubscribeDataSetArguments, _
   ByVal waitMilliseconds As Integer _
) As Task
'Usage
 
Dim subscriber As IEasyUASubscriber
Dim subscribeDataSetArguments As UASubscribeDataSetArguments
Dim waitMilliseconds As Integer
Dim value As Task
 
value = IEasyUASubscriberExtension2.TestConnectionAsync(subscriber, subscribeDataSetArguments, waitMilliseconds)
[Extension()]
[AsyncThrows(OpcLabs.EasyOpc.UA.OperationModel.UAException)]
[NotNull()]
public static Task TestConnectionAsync( 
   IEasyUASubscriber subscriber,
   UASubscribeDataSetArguments subscribeDataSetArguments,
   int waitMilliseconds
)
[Extension()]
[AsyncThrows(OpcLabs.EasyOpc.UA.OperationModel.UAException)]
[NotNull()]
public:
static Task^ TestConnectionAsync( 
   IEasyUASubscriber^ subscriber,
   UASubscribeDataSetArguments^ subscribeDataSetArguments,
   int waitMilliseconds
) 

Parameters

subscriber
The subscriber object that will perform the operation.
subscribeDataSetArguments
Holds all arguments needed to subscribe to a dataset in OPC UA PubSub.
waitMilliseconds
Number of milliseconds to wait before the connection test can pass.
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

Due to asynchronous nature of some communication channels, successful test outcome does not always imply that a connection has been fully established.

The waitMilliseconds parameter is not a timeout in its traditional sense, i.e. a maximum time allowed for the operation. Here, this method actually waits for the time given by waitMilliseconds parameter unless a failure occurs.

This is an asynchronous method. For a synchronous alternative, see TestConnection(IEasyUASubscriber,UASubscribeDataSetArguments,Int32).

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