Expression.Loop Metode

Definisi

Ruang nama:

System.Linq.Expressions

Rakitan:

System.Linq.Expressions.dll

LoopExpressionMembuat .

Overload

Loop(Expression)	LoopExpression Membuat dengan isi yang diberikan.
Loop(Expression, LabelTarget)	Membuat dengan isi yang LoopExpression diberikan dan memutus target.
Loop(Expression, LabelTarget, LabelTarget)	LoopExpression Membuat dengan isi yang diberikan.

Loop(Expression)

Sumber:

LoopExpression.cs

LoopExpression Membuat dengan isi yang diberikan.

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

Parameter

body

Expression

Tubuh perulangan.

Mengembalikan

LoopExpression

yang dibuat LoopExpression.

Loop(Expression, LabelTarget)

Sumber:

LoopExpression.cs

Membuat dengan isi yang LoopExpression diberikan dan memutus 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

Parameter

body

Expression

Tubuh perulangan.

break

LabelTarget

Target pemutusan yang digunakan oleh isi perulangan.

Mengembalikan

LoopExpression

yang dibuat LoopExpression.

Contoh

Contoh berikut menunjukkan cara membuat ekspresi blok yang berisi LoopExpression objek .

// 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)

Sumber:

LoopExpression.cs

LoopExpression Membuat dengan isi yang diberikan.

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

Parameter

body

Expression

Tubuh perulangan.

break

LabelTarget

Target pemutusan yang digunakan oleh isi perulangan.

continue

LabelTarget

Target lanjutan yang digunakan oleh isi perulangan.

Mengembalikan

LoopExpression

yang dibuat LoopExpression.