GotoExpression Class

Represents an unconditional jump. This includes return statements, break and continue statements, and other jumps.

System.Object
  System.Linq.Expressions.Expression
    System.Linq.Expressions.GotoExpression

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

public sealed class GotoExpression : Expression

The GotoExpression type exposes the following members.

  NameDescription
Public propertySupported by Portable Class LibraryCanReduceIndicates that the node can be reduced to a simpler node. If this returns true, Reduce() can be called to produce the reduced form. (Inherited from Expression.)
Public propertySupported by Portable Class LibraryKindThe kind of the "go to" expression. Serves information purposes only.
Public propertySupported by Portable Class LibraryNodeTypeReturns the node type of this Expression. (Overrides Expression.NodeType.)
Public propertySupported by Portable Class LibraryTargetThe target label where this node jumps to.
Public propertySupported by Portable Class LibraryTypeGets the static type of the expression that this Expression represents. (Overrides Expression.Type.)
Public propertySupported by Portable Class LibraryValueThe value passed to the target, or null if the target is of type System.Void.
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  NameDescription
Protected methodSupported by Portable Class LibraryAcceptDispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall. (Inherited from Expression.)
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 LibraryReduceReduces this node to a simpler expression. If CanReduce returns true, this should return a valid expression. This method can return another node which itself must be reduced. (Inherited from Expression.)
Public methodSupported by Portable Class LibraryReduceAndCheckReduces this node to a simpler expression. If CanReduce returns true, this should return a valid expression. This method can return another node which itself must be reduced. (Inherited from Expression.)
Public methodSupported by Portable Class LibraryReduceExtensionsReduces the expression to a known node type (that is not an Extension node) or just returns the expression if it is already a known type. (Inherited from Expression.)
Public methodSupported by Portable Class LibraryToStringReturns a textual representation of the Expression. (Inherited from Expression.)
Public methodSupported by Portable Class LibraryUpdateCreates a new expression that is like this one, but using the supplied children. If all of the children are the same, it will return this expression.
Protected methodSupported by Portable Class LibraryVisitChildrenReduces the node and then calls the visitor delegate on the reduced expression. The method throws an exception if the node is not reducible. (Inherited from Expression.)
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The following example demonstrates how to create an expression that contains a GotoExpression object by using the Goto method.

// Add the following directive to your file: 
// using System.Linq.Expressions;   

// A label expression of the void type that is the target for the GotoExpression.
LabelTarget returnTarget = Expression.Label();

// This block contains a GotoExpression. 
// 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("GoTo")),
        Expression.Goto(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: 
// 
// GoTo 

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

.NET Framework

Supported in: 4.6, 4.5, 4

.NET Framework Client Profile

Supported in: 4

.NET for Windows Phone apps

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

Portable Class Library

Supported in: Portable Class Library

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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