ParameterExpression Sınıf

Tanım

public ref class ParameterExpression : System::Linq::Expressions::Expression

public ref class ParameterExpression sealed : System::Linq::Expressions::Expression

public class ParameterExpression : System.Linq.Expressions.Expression

public sealed class ParameterExpression : System.Linq.Expressions.Expression

type ParameterExpression = class
    inherit Expression

Public Class ParameterExpression
Inherits Expression

Public NotInheritable Class ParameterExpression
Inherits Expression

Devralma

Object

Expression

ParameterExpression

Örnekler

Aşağıdaki örnek, yöntemini kullanarak Parameter bir MethodCallExpression nesnenin değerini yazdıran bir ParameterExpression nesnenin nasıl oluşturulacağını gösterir.

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

// Creating a parameter for the expression tree.
ParameterExpression param = Expression.Parameter(typeof(int));

// Creating an expression for the method call and specifying its parameter.
MethodCallExpression methodCall = Expression.Call(
    typeof(Console).GetMethod("WriteLine", new Type[] { typeof(int) }),
    param
);

// The following statement first creates an expression tree,
// then compiles it, and then runs it.
Expression.Lambda<Action<int>>(
    methodCall,
    new ParameterExpression[] { param }
).Compile()(10);

// This code example produces the following output:
//
// 10

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

' Creating a parameter for the expression tree.
Dim param As ParameterExpression = Expression.Parameter(GetType(Integer))

' Creating an expression for the method call and specifying its parameter.
Dim methodCall As MethodCallExpression = Expression.Call(
        GetType(Console).GetMethod("WriteLine", New Type() {GetType(Integer)}),
        param
    )

' Compiling and invoking the methodCall expression.
Expression.Lambda(Of Action(Of Integer))(
    methodCall,
    New ParameterExpression() {param}
).Compile()(10)
' This code example produces the following output:
'
' 10

Açıklamalar

Parameter oluşturmak ParameterExpressioniçin fabrika yöntemini kullanın.

Bir ParameterExpression nesnenin NodeType özelliğinin değeri şeklindedirParameter.

Özellikler

Yöntemler

Şunlara uygulanır