SubscribeTarget(DAClientMapper,Boolean,Predicate<IEnumerable<String>>,Object,Boolean) Method

Executes the "Subscribe" operation on members of given target object.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
<ExtensionAttribute()>
Public Overloads Shared Sub SubscribeTarget( _
   ByVal clientMapper As DAClientMapper, _
   ByVal active As Boolean, _
   ByVal mappingTagsPredicate As Predicate(Of IEnumerable(Of String)), _
   ByVal targetObject As Object, _
   ByVal recurse As Boolean _
)

'Usage
 
Dim clientMapper As DAClientMapper
Dim active As Boolean
Dim mappingTagsPredicate As Predicate(Of IEnumerable(Of String))
Dim targetObject As Object
Dim recurse As Boolean
 
DAClientMapperExtension.SubscribeTarget(clientMapper, active, mappingTagsPredicate, targetObject, recurse)

[Extension()]
public static void SubscribeTarget( 
   DAClientMapper clientMapper,
   bool active,
   Predicate<IEnumerable<string>> mappingTagsPredicate,
   object targetObject,
   bool recurse
)

[Extension()]
public:
static void SubscribeTarget( 
   DAClientMapper^ clientMapper,
   bool active,
   Predicate<IEnumerable<String^>^>^ mappingTagsPredicate,
   Object^ targetObject,
   bool recurse
)

Parameters

clientMapper: The client mapper object that will perform the operation.
active: true to subscribe; false to unsubscribe.
mappingTagsPredicate: The operation will be performed only on mappings whose mapping tags satisfy this predicate.
targetObject: The object being targeted.
recurse: true to operate on sub-targets (mapped members of the target) recursively; false otherwise.

Exceptions

Exception Description

Exception	Description
System.ArgumentNullException	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.
OpcLabs.BaseLib.Licensing.LicensingException	The component is not licensed for the operation requested.

System.ArgumentNullException

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.

OpcLabs.BaseLib.Licensing.LicensingException The component is not licensed for the operation requested.

Remarks

The "Subscribe" operation subscribes to or unsubscribes from changes of an OPC item. Only mappings of type OpcLabs.EasyOpc.DataAccess.LiveMapping.DAItemMapping that include OpcLabs.EasyOpc.DataAccess.LiveMapping.DAItemMappingOperations.Subscribe in their OpcLabs.EasyOpc.DataAccess.LiveMapping.DAClientItemMapping.Operations are affected; other mappings are ignored.

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

DAClientMapperExtension Class
DAClientMapperExtension Members
Overload List

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