Expression.Break Metodo

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

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

Parametri

Valori restituiti

Oggetto GotoExpression con Kind uguale a Break, la Target proprietà impostata su targete un valore Null da passare all'etichetta di destinazione al momento del salto.

Esempio

Nell'esempio seguente viene illustrato come creare un'espressione contenente un LoopExpression oggetto che usa il Break metodo .

// 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

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

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

Parametri

Valori restituiti

Oggetto GotoExpression con Kind uguale a Break, la Target proprietà impostata su targete value da passare all'etichetta di destinazione al momento del salto.

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

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

Parametri

Valori restituiti

Oggetto GotoExpression con Kind uguale a Break, la Target proprietà impostata su targete la Type proprietà impostata su type.

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

GotoExpression.cs

Origine:

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

Parametri

Valori restituiti

Oggetto GotoExpression con Kind uguale a Break, la Target proprietà impostata su target, la Type proprietà impostata su typee value da passare all'etichetta di destinazione al momento del salto.