Expression.Loop Expression.Loop Expression.Loop Expression.Loop Method

Definition

Creates a LoopExpression.

Overloads

Loop(Expression) Loop(Expression) Loop(Expression) Loop(Expression)

Creates a LoopExpression with the given body.

Loop(Expression, LabelTarget) Loop(Expression, LabelTarget) Loop(Expression, LabelTarget) Loop(Expression, LabelTarget)

Creates a LoopExpression with the given body and break target.

Loop(Expression, LabelTarget, LabelTarget) Loop(Expression, LabelTarget, LabelTarget) Loop(Expression, LabelTarget, LabelTarget) Loop(Expression, LabelTarget, LabelTarget)

Creates a LoopExpression with the given body.

Loop(Expression) Loop(Expression) Loop(Expression) Loop(Expression)

Creates a LoopExpression with the given body.

public:
 static System::Linq::Expressions::LoopExpression ^ Loop(System::Linq::Expressions::Expression ^ body);
public static System.Linq.Expressions.LoopExpression Loop (System.Linq.Expressions.Expression body);
static member Loop : System.Linq.Expressions.Expression -> System.Linq.Expressions.LoopExpression
Public Shared Function Loop (body As Expression) As LoopExpression

Parameters

body
Expression Expression Expression Expression

The body of the loop.

Returns

Loop(Expression, LabelTarget) Loop(Expression, LabelTarget) Loop(Expression, LabelTarget) Loop(Expression, LabelTarget)

Creates a LoopExpression with the given body and break target.

public:
 static System::Linq::Expressions::LoopExpression ^ Loop(System::Linq::Expressions::Expression ^ body, System::Linq::Expressions::LabelTarget ^ break);
public static System.Linq.Expressions.LoopExpression Loop (System.Linq.Expressions.Expression body, System.Linq.Expressions.LabelTarget break);
static member Loop : System.Linq.Expressions.Expression * System.Linq.Expressions.LabelTarget -> System.Linq.Expressions.LoopExpression
Public Shared Function Loop (body As Expression, break As LabelTarget) As LoopExpression

Parameters

body
Expression Expression Expression Expression

The body of the loop.

break
LabelTarget LabelTarget LabelTarget LabelTarget

The break target used by the loop body.

Returns

Examples

The following example demonstrates how to create a block expression that contains a LoopExpression object.

// 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

Loop(Expression, LabelTarget, LabelTarget) Loop(Expression, LabelTarget, LabelTarget) Loop(Expression, LabelTarget, LabelTarget) Loop(Expression, LabelTarget, LabelTarget)

Creates a LoopExpression with the given body.

public:
 static System::Linq::Expressions::LoopExpression ^ Loop(System::Linq::Expressions::Expression ^ body, System::Linq::Expressions::LabelTarget ^ break, System::Linq::Expressions::LabelTarget ^ continue);
public static System.Linq.Expressions.LoopExpression Loop (System.Linq.Expressions.Expression body, System.Linq.Expressions.LabelTarget break, System.Linq.Expressions.LabelTarget continue);
static member Loop : System.Linq.Expressions.Expression * System.Linq.Expressions.LabelTarget * System.Linq.Expressions.LabelTarget -> System.Linq.Expressions.LoopExpression
Public Shared Function Loop (body As Expression, break As LabelTarget, continue As LabelTarget) As LoopExpression

Parameters

body
Expression Expression Expression Expression

The body of the loop.

break
LabelTarget LabelTarget LabelTarget LabelTarget

The break target used by the loop body.

continue
LabelTarget LabelTarget LabelTarget LabelTarget

The continue target used by the loop body.

Returns

Applies to