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LabelTarget Class

Used to represent the target of a GotoExpression.

System.Object
  System.Linq.Expressions.LabelTarget

Namespace:  System.Linq.Expressions
Assembly:  System.Core (in System.Core.dll)

'Declaration
Public NotInheritable Class LabelTarget

The LabelTarget type exposes the following members.

  NameDescription
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsNameGets the name of the label.
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsTypeThe type of value that is passed when jumping to the label (or Void if no value should be passed).
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  NameDescription
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsToStringReturns a String that represents the current Object. (Overrides Object.ToString.)
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The following example demonstrates how to create an expression that contains a LabelTarget object by using the Label method.

' Add the following directive to the file: 
' Imports System.Linq.Expressions   
' A label expression of the void type that is the target for Expression.Return(). 
Dim returnTarget As LabelTarget = Expression.Label()

' This block contains a GotoExpression that represents a return statement with no value. 
' It transfers execution to a label expression that is initialized with the same LabelTarget as the GotoExpression. 
' The types of the GotoExpression, label expression, and LabelTarget must match. 
Dim blockExpr As BlockExpression =
      Expression.Block(
          Expression.Call(GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}), Expression.Constant("Return")),
          Expression.Return(returnTarget),
          Expression.Call(GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}), Expression.Constant("Other Work")),
          Expression.Label(returnTarget)
      )

' The following statement first creates an expression tree, 
' then compiles it, and then runs it.
Expression.Lambda(Of Action)(blockExpr).Compile()()

' This code example produces the following output: 

' Return 

' "Other Work" is not printed because  
' the Return expression transfers execution from Return(returnTarget) 
' to Expression.Label(returnTarget).

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4

.NET Framework Client Profile

Supported in: 4

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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