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Expression.Break Method

Definition

Creates a GotoExpression representing a break statement.

Overloads

Break(LabelTarget)

Creates a GotoExpression representing a break statement.

Break(LabelTarget, Expression)

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

Break(LabelTarget, Type)

Creates a GotoExpression representing a break statement with the specified type.

Break(LabelTarget, Expression, Type)

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

Break(LabelTarget)

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

Creates a GotoExpression representing a break statement.

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

Parameters

target
LabelTarget

The LabelTarget that the GotoExpression will jump to.

Returns

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.

Examples

The following example demonstrates how to create an expression that contains a LoopExpression object that uses the Break method.

// 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

Applies to

Break(LabelTarget, Expression)

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

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

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

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 Break, the Target property set to target, and value to be passed to the target label upon jumping.

Applies to

Break(LabelTarget, Type)

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

Creates a GotoExpression representing a break statement with the specified type.

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

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 Break, the Target property set to target, and the Type property set to type.

Applies to

Break(LabelTarget, Expression, Type)

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

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

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

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 Break, 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