Expression.Break Methode

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

public:
 static System::Linq::Expressions::GotoExpression ^ Break(System::Linq::Expressions::LabelTarget ^ target);

public static System.Linq.Expressions.GotoExpression Break(System.Linq.Expressions.LabelTarget target);

static member Break : System.Linq.Expressions.LabelTarget -> System.Linq.Expressions.GotoExpression

Public Shared Function Break (target As LabelTarget) As GotoExpression

Parameter

Gibt zurück

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

Beispiele

Im folgenden Beispiel wird das Erstellen eines Ausdrucks veranschaulicht, der ein LoopExpression Objekt enthält, das die Break Methode verwendet.

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

// Creating a parameter expression.
ParameterExpression value = Expression.Parameter(typeof(int), "value");

// Creating an expression to hold a local variable.
ParameterExpression result = Expression.Parameter(typeof(int), "result");

// Creating a label to jump to from a loop.
LabelTarget label = Expression.Label(typeof(int));

// Creating a method body.
BlockExpression block = Expression.Block(
    new[] { result },
    Expression.Assign(result, Expression.Constant(1)),
        Expression.Loop(
           Expression.IfThenElse(
               Expression.GreaterThan(value, Expression.Constant(1)),
               Expression.MultiplyAssign(result,
                   Expression.PostDecrementAssign(value)),
               Expression.Break(label, result)
           ),
       label
    )
);

// Compile and run an expression tree.
int factorial = Expression.Lambda<Func<int, int>>(block, value).Compile()(5);

Console.WriteLine(factorial);

// This code example produces the following output:
//
// 120

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

' Creating a parameter expression.
Dim value As ParameterExpression =
    Expression.Parameter(GetType(Integer), "value")

' Creating an expression to hold a local variable. 
Dim result As ParameterExpression =
    Expression.Parameter(GetType(Integer), "result")

' Creating a label to jump to from a loop.
Dim label As LabelTarget = Expression.Label(GetType(Integer))

' Creating a method body.
Dim block As BlockExpression = Expression.Block(
    New ParameterExpression() {result},
    Expression.Assign(result, Expression.Constant(1)),
    Expression.Loop(
        Expression.IfThenElse(
            Expression.GreaterThan(value, Expression.Constant(1)),
            Expression.MultiplyAssign(result,
                Expression.PostDecrementAssign(value)),
            Expression.Break(label, result)
        ),
        label
    )
)

' Compile an expression tree and return a delegate.
Dim factorial As Integer =
    Expression.Lambda(Of Func(Of Integer, Integer))(block, value).Compile()(5)

Console.WriteLine(factorial)

' This code example produces the following output:
'
' 120

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

public:
 static System::Linq::Expressions::GotoExpression ^ Break(System::Linq::Expressions::LabelTarget ^ target, System::Linq::Expressions::Expression ^ value);

public static System.Linq.Expressions.GotoExpression Break(System.Linq.Expressions.LabelTarget target, System.Linq.Expressions.Expression value);

public static System.Linq.Expressions.GotoExpression Break(System.Linq.Expressions.LabelTarget target, System.Linq.Expressions.Expression? value);

static member Break : System.Linq.Expressions.LabelTarget * System.Linq.Expressions.Expression -> System.Linq.Expressions.GotoExpression

Public Shared Function Break (target As LabelTarget, value As Expression) As GotoExpression

Parameter

Gibt zurück

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

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

public:
 static System::Linq::Expressions::GotoExpression ^ Break(System::Linq::Expressions::LabelTarget ^ target, Type ^ type);

public static System.Linq.Expressions.GotoExpression Break(System.Linq.Expressions.LabelTarget target, Type type);

static member Break : System.Linq.Expressions.LabelTarget * Type -> System.Linq.Expressions.GotoExpression

Public Shared Function Break (target As LabelTarget, type As Type) As GotoExpression

Parameter

Gibt zurück

A GotoExpression with Kind equal to Break, the Target property set to target, and the Type property set to type.

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

Quelle:

GotoExpression.cs

public:
 static System::Linq::Expressions::GotoExpression ^ Break(System::Linq::Expressions::LabelTarget ^ target, System::Linq::Expressions::Expression ^ value, Type ^ type);

public static System.Linq.Expressions.GotoExpression Break(System.Linq.Expressions.LabelTarget target, System.Linq.Expressions.Expression value, Type type);

public static System.Linq.Expressions.GotoExpression Break(System.Linq.Expressions.LabelTarget target, System.Linq.Expressions.Expression? value, Type type);

static member Break : System.Linq.Expressions.LabelTarget * System.Linq.Expressions.Expression * Type -> System.Linq.Expressions.GotoExpression

Public Shared Function Break (target As LabelTarget, value As Expression, type As Type) As GotoExpression

Parameter

Gibt zurück

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