संपादित करें

इसके माध्यम से साझा किया गया


Expression.Goto Method

Definition

Creates a GotoExpression representing a "go to" statement.

Overloads

Goto(LabelTarget, Expression, Type)

Creates a GotoExpression representing a "go to" statement with the specified type. The value passed to the label upon jumping can be specified.

Goto(LabelTarget, Type)

Creates a GotoExpression representing a "go to" statement with the specified type.

Goto(LabelTarget)

Creates a GotoExpression representing a "go to" statement.

Goto(LabelTarget, Expression)

Creates a GotoExpression representing a "go to" statement. The value passed to the label upon jumping can be specified.

Goto(LabelTarget, Expression, Type)

Source:
GotoExpression.cs
Source:
GotoExpression.cs
Source:
GotoExpression.cs

Creates a GotoExpression representing a "go to" statement with the specified type. The value passed to the label upon jumping can be specified.

public:
 static System::Linq::Expressions::GotoExpression ^ Goto(System::Linq::Expressions::LabelTarget ^ target, System::Linq::Expressions::Expression ^ value, Type ^ type);
public static System.Linq.Expressions.GotoExpression Goto (System.Linq.Expressions.LabelTarget target, System.Linq.Expressions.Expression value, Type type);
public static System.Linq.Expressions.GotoExpression Goto (System.Linq.Expressions.LabelTarget target, System.Linq.Expressions.Expression? value, Type type);
static member Goto : System.Linq.Expressions.LabelTarget * System.Linq.Expressions.Expression * Type -> System.Linq.Expressions.GotoExpression
Public Shared Function Goto (target As LabelTarget, value As Expression, type As Type) As GotoExpression

Parameters

target
LabelTarget

The LabelTarget that the GotoExpression will jump to.

value
Expression

The value that will be passed to the associated label upon jumping.

type
Type

An Type to set the Type property equal to.

Returns

A GotoExpression with Kind equal to Goto, the Target property set to target, the Type property set to type, and value to be passed to the target label upon jumping.

Applies to

Goto(LabelTarget, Type)

Source:
GotoExpression.cs
Source:
GotoExpression.cs
Source:
GotoExpression.cs

Creates a GotoExpression representing a "go to" statement with the specified type.

public:
 static System::Linq::Expressions::GotoExpression ^ Goto(System::Linq::Expressions::LabelTarget ^ target, Type ^ type);
public static System.Linq.Expressions.GotoExpression Goto (System.Linq.Expressions.LabelTarget target, Type type);
static member Goto : System.Linq.Expressions.LabelTarget * Type -> System.Linq.Expressions.GotoExpression
Public Shared Function Goto (target As LabelTarget, type As Type) As GotoExpression

Parameters

target
LabelTarget

The LabelTarget that the GotoExpression will jump to.

type
Type

An Type to set the Type property equal to.

Returns

A GotoExpression with Kind equal to Goto, the Target property set to the specified value, the Type property set to type, and a null value to be passed to the target label upon jumping.

Applies to

Goto(LabelTarget)

Source:
GotoExpression.cs
Source:
GotoExpression.cs
Source:
GotoExpression.cs

Creates a GotoExpression representing a "go to" statement.

public:
 static System::Linq::Expressions::GotoExpression ^ Goto(System::Linq::Expressions::LabelTarget ^ target);
public static System.Linq.Expressions.GotoExpression Goto (System.Linq.Expressions.LabelTarget target);
static member Goto : System.Linq.Expressions.LabelTarget -> System.Linq.Expressions.GotoExpression
Public Shared Function Goto (target As LabelTarget) As GotoExpression

Parameters

target
LabelTarget

The LabelTarget that the GotoExpression will jump to.

Returns

A GotoExpression with Kind equal to Goto, the Target property set to the specified value, and a null value to be passed to the target label upon jumping.

Examples

The following example demonstrates how to create an expression that contains a GotoExpression object.

// 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).
' Add the following directive to your file:
' Imports System.Linq.Expressions  

' A label expression of the void type that is the target for the GoToExpression.
Dim returnTarget As LabelTarget = 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.
Dim blockExpr As BlockExpression =
      Expression.Block(
          Expression.Call(GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}), Expression.Constant("GoTo")),
          Expression.Goto(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:
'
' GoTo

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

Applies to

Goto(LabelTarget, Expression)

Source:
GotoExpression.cs
Source:
GotoExpression.cs
Source:
GotoExpression.cs

Creates a GotoExpression representing a "go to" statement. The value passed to the label upon jumping can be specified.

public:
 static System::Linq::Expressions::GotoExpression ^ Goto(System::Linq::Expressions::LabelTarget ^ target, System::Linq::Expressions::Expression ^ value);
public static System.Linq.Expressions.GotoExpression Goto (System.Linq.Expressions.LabelTarget target, System.Linq.Expressions.Expression value);
public static System.Linq.Expressions.GotoExpression Goto (System.Linq.Expressions.LabelTarget target, System.Linq.Expressions.Expression? value);
static member Goto : System.Linq.Expressions.LabelTarget * System.Linq.Expressions.Expression -> System.Linq.Expressions.GotoExpression
Public Shared Function Goto (target As LabelTarget, value As Expression) As GotoExpression

Parameters

target
LabelTarget

The LabelTarget that the GotoExpression will jump to.

value
Expression

The value that will be passed to the associated label upon jumping.

Returns

A GotoExpression with Kind equal to Goto, the Target property set to target, and value to be passed to the target label upon jumping.

Applies to