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)

public sealed class LabelTarget

The LabelTarget type exposes the following members.

  NameDescription
Public propertySupported by Portable Class LibraryNameGets the name of the label.
Public propertySupported by Portable Class LibraryTypeThe 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 LibraryEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Public methodSupported by Portable Class LibraryGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodSupported by Portable Class LibraryGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodSupported by Portable Class LibraryToStringReturns 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: 
// using System.Linq.Expressions;   

// A label expression of the void type that is the target for Expression.Return().
LabelTarget returnTarget = 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.
BlockExpression blockExpr =
    Expression.Block(
        Expression.Call(typeof(Console).GetMethod("WriteLine", new Type[] { typeof(string) }), Expression.Constant("Return")),
        Expression.Return(returnTarget),
        Expression.Call(typeof(Console).GetMethod("WriteLine", new Type[] { typeof(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<Action>(blockExpr).Compile()();

// This code example produces the following output: 
// 
// Return 

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

.NET Framework

Supported in: 4.6, 4.5, 4

.NET Framework Client Profile

Supported in: 4

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8

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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