FromExternalValue(Object) Method

Converts an external value into a publisher Id.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<NotNullAttribute()>
<PureAttribute()>
Public Shared Function FromExternalValue( _
   ByVal externalValue As Object _
) As UAPublisherId

'Usage
 
Dim externalValue As Object
Dim value As UAPublisherId
 
value = UAPublisherId.FromExternalValue(externalValue)

[NotNull()]
[Pure()]
public static UAPublisherId FromExternalValue( 
   object externalValue
)

[NotNull()]
[Pure()]
public:
static UAPublisherId^ FromExternalValue( 
   Object^ externalValue
)

Parameters

externalValue: External value of the publisher Id identifier.
The value of this parameter can be null (Nothing in Visual Basic).

Return Value

Returns a publisher Id with the specified external value.

Because the UASubscribeDataSetFilter has an implicit conversion from UAPublisherId, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use the returned UAPublisherId (containing the publisher Id that you want to allow in the filter) in any place where UASubscribeDataSetFilter is expected as input, and the corresponding OPC UA subscribe dataset filter will be constructed automatically. When the implicit conversion operators are not supported (such as with Python.NET), you can use the UASubscribeDataSetFilter.FromUAPublisherId static method instead.

This method never returns null (Nothing in Visual Basic).

Remarks

External value is a CLS-compliant value used e.g. when accessing the publisher ID over OpcLabs.EasyOpc.UA.IEasyUAClient. It is System.Byte, System.Int32, System.Int64, System.Decimal, System.String, or null.

This method is pure, i.e. it does not have observable side effects.

Requirements

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

Reference

UAPublisherId Class
UAPublisherId Members

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