語言

Expression.Return 方法

定義

建立 GotoExpression 一個代表返回語句的表示。

多載

名稱 Description
Return(LabelTarget)

建立 GotoExpression 一個代表返回語句的表示。

Return(LabelTarget, Expression)

建立 GotoExpression 一個代表返回語句的表示。 跳躍時傳遞給標籤的值可以指定。

Return(LabelTarget, Type)

建立 GotoExpression 一個代表指定型別的回傳語句。

Return(LabelTarget, Expression, Type)

建立 GotoExpression 一個代表指定型別的回傳語句。 跳躍時傳遞給標籤的值可以指定。

Return(LabelTarget)

來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs

建立 GotoExpression 一個代表返回語句的表示。

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

參數

target
LabelTarget

LabelTarget他們會跳到那GotoExpression個地方。

傳回

GotoExpression一個等Kind於 Return,Target屬性設為 target,跳躍時要傳遞一個空值給目標標籤。

適用於

Return(LabelTarget, Expression)

來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs

建立 GotoExpression 一個代表返回語句的表示。 跳躍時傳遞給標籤的值可以指定。

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

參數

target
LabelTarget

LabelTarget他們會跳到那GotoExpression個地方。

value
Expression

跳轉時會傳遞給相關標籤的值。

傳回

GotoExpression A 等Kind於 Continue,Target將屬性設為 target,跳value躍時傳遞給目標標籤。

範例

以下範例示範如何建立包含該 Return 方法的表達式。

// 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).
' 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).

適用於

Return(LabelTarget, Type)

來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs

建立 GotoExpression 一個代表指定型別的回傳語句。

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

參數

target
LabelTarget

LabelTarget他們會跳到那GotoExpression個地方。

type
Type

Type A 將屬性Type設為 。

傳回

A GotoExpression 中 Kind 等於 Return, Target 屬性設 target為 , Type 屬性設為 type,跳躍時傳送一個空值。

適用於

Return(LabelTarget, Expression, Type)

來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs
來源:
GotoExpression.cs

建立 GotoExpression 一個代表指定型別的回傳語句。 跳躍時傳遞給標籤的值可以指定。

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

參數

target
LabelTarget

LabelTarget他們會跳到那GotoExpression個地方。

value
Expression

跳轉時會傳遞給相關標籤的值。

type
Type

Type A 將屬性Type設為 。

傳回

GotoExpression A 等Kind於 Continue,Target屬性設target為 ,屬性設為 ,Type屬性設為 type,value跳躍時傳給目標標籤。

適用於