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MethodCallExpression Class

Definition

Represents a call to either static or an instance method.

public ref class MethodCallExpression : System::Linq::Expressions::Expression, System::Linq::Expressions::IArgumentProvider
public ref class MethodCallExpression sealed : System::Linq::Expressions::Expression
public ref class MethodCallExpression : System::Linq::Expressions::Expression
public class MethodCallExpression : System.Linq.Expressions.Expression, System.Linq.Expressions.IArgumentProvider
public sealed class MethodCallExpression : System.Linq.Expressions.Expression
public class MethodCallExpression : System.Linq.Expressions.Expression
type MethodCallExpression = class
    inherit Expression
    interface IArgumentProvider
type MethodCallExpression = class
    inherit Expression
Public Class MethodCallExpression
Inherits Expression
Implements IArgumentProvider
Public NotInheritable Class MethodCallExpression
Inherits Expression
Public Class MethodCallExpression
Inherits Expression
Inheritance
MethodCallExpression
Implements

Examples

The following example creates a MethodCallExpression object that represents indexing into a two-dimensional array.

string[,] gradeArray =
    { {"chemistry", "history", "mathematics"}, {"78", "61", "82"} };

System.Linq.Expressions.Expression arrayExpression =
    System.Linq.Expressions.Expression.Constant(gradeArray);

// Create a MethodCallExpression that represents indexing
// into the two-dimensional array 'gradeArray' at (0, 2).
// Executing the expression would return "mathematics".
System.Linq.Expressions.MethodCallExpression methodCallExpression =
    System.Linq.Expressions.Expression.ArrayIndex(
        arrayExpression,
        System.Linq.Expressions.Expression.Constant(0),
        System.Linq.Expressions.Expression.Constant(2));

Console.WriteLine(methodCallExpression.ToString());

// This code produces the following output:
//
// value(System.String[,]).Get(0, 2)
Dim gradeArray(,) As String = _
    {{"chemistry", "history", "mathematics"}, {"78", "61", "82"}}

Dim arrayExpression As System.Linq.Expressions.Expression = _
    System.Linq.Expressions.Expression.Constant(gradeArray)

' Create a MethodCallExpression that represents indexing
' into the two-dimensional array 'gradeArray' at (0, 2).
' Executing the expression would return "mathematics".
Dim methodCallExpression As System.Linq.Expressions.MethodCallExpression = _
    System.Linq.Expressions.Expression.ArrayIndex( _
        arrayExpression, _
        System.Linq.Expressions.Expression.Constant(0), _
        System.Linq.Expressions.Expression.Constant(2))

Console.WriteLine(methodCallExpression.ToString())

' This code produces the following output:
'
' value(System.String[,]).Get(0, 2)

Remarks

Use the Call, ArrayIndex, or ArrayIndex factory method to create a MethodCallExpression.

The value of the NodeType property of a MethodCallExpression object is Call.

Properties

Arguments

Gets a collection of expressions that represent arguments of the called method.

CanReduce

Indicates that the node can be reduced to a simpler node. If this returns true, Reduce() can be called to produce the reduced form.

(Inherited from Expression)
Method

Gets the MethodInfo for the method to be called.

NodeType

Returns the node type of this Expression.

NodeType

Gets the node type of this Expression.

(Inherited from Expression)
Object

Gets the Expression that represents the instance for instance method calls or null for static method calls.

Type

Gets the static type of the expression that this Expression represents.

Type

Gets the static type of the expression that this Expression represents.

(Inherited from Expression)

Methods

Accept(ExpressionVisitor)

Dispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall(MethodCallExpression).

Accept(ExpressionVisitor)

Dispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall(MethodCallExpression).

(Inherited from Expression)
Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
Reduce()

Reduces this node to a simpler expression. If CanReduce returns true, this should return a valid expression. This method can return another node which itself must be reduced.

(Inherited from Expression)
ReduceAndCheck()

Reduces this node to a simpler expression. If CanReduce returns true, this should return a valid expression. This method can return another node which itself must be reduced.

(Inherited from Expression)
ReduceExtensions()

Reduces the expression to a known node type (that is not an Extension node) or just returns the expression if it is already a known type.

(Inherited from Expression)
ToString()

Returns a textual representation of the Expression.

(Inherited from Expression)
Update(Expression, IEnumerable<Expression>)

Creates a new expression that is like this one, but using the supplied children. If all of the children are the same, it will return this expression.

VisitChildren(ExpressionVisitor)

Reduces the node and then calls the visitor delegate on the reduced expression. The method throws an exception if the node is not reducible.

(Inherited from Expression)

Explicit Interface Implementations

IArgumentProvider.ArgumentCount

Returns the number of arguments to the expression tree node. You should not use this member. It is only public due to assembly refactoring, and it is used internally for performance optimizations.

IArgumentProvider.GetArgument(Int32)

Returns the argument at index, throwing if index is out of bounds. You should not use this member. It is only public due to assembly refactoring, and it is used internally for performance optimizations.

Applies to