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Expression.Call Method (Expression, MethodInfo, array<Expression[])

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Creates a MethodCallExpression that represents a call to a method that takes arguments.

Namespace:  System.Linq.Expressions
Assembly:  System.Core (in System.Core.dll)

Syntax

'Declaration
Public Shared Function Call ( _
    instance As Expression, _
    method As MethodInfo, _
    ParamArray arguments As Expression() _
) As MethodCallExpression
public static MethodCallExpression Call(
    Expression instance,
    MethodInfo method,
    params Expression[] arguments
)

Parameters

  • instance
    Type: System.Linq.Expressions.Expression
    An Expression that specifies the instance fo an instance method call (pass nulla null reference (Nothing in Visual Basic) for a static (Shared in Visual Basic) method).

Return Value

Type: System.Linq.Expressions.MethodCallExpression
A MethodCallExpression that has the NodeType property equal to Call and the Object, Method, and Arguments properties set to the specified values.

Exceptions

Exception Condition
ArgumentNullException

method is nulla null reference (Nothing in Visual Basic).

-or-

instance is nulla null reference (Nothing in Visual Basic) and method represents an instance method.

-or-

arguments is not nulla null reference (Nothing in Visual Basic) and one or more of its elements is nulla null reference (Nothing in Visual Basic).

ArgumentException

instance.Type is not assignable to the declaring type of the method represented by method.

-or-

The number of elements in arguments does not equal the number of parameters for the method represented by method.

-or-

One or more of the elements of arguments is not assignable to the corresponding parameter for the method represented by method.

Remarks

To represent a call to a static (Shared in Visual Basic) method, pass in nulla null reference (Nothing in Visual Basic) for the instance parameter when you call this method, or call Call instead.

If method represents an instance method, the Type property of instance must be assignable to the declaring type of the method represented by method.

If arguments is not nulla null reference (Nothing in Visual Basic), it must have the same number of elements as the number of parameters for the method represented by method. Each element in arguments must not be nulla null reference (Nothing in Visual Basic) and must be assignable to the corresponding parameter of method, possibly after quoting.

NoteNote:

An element will be quoted only if the corresponding method parameter is of type Expression. Quoting means the element is wrapped in a Quote node. The resulting node is a UnaryExpression whose Operand property is the element of arguments.

The Arguments property of the resulting MethodCallExpression is empty if arguments is nulla null reference (Nothing in Visual Basic). Otherwise, it contains the same elements as arguments, some of which may be quoted.

The Type property of the resulting MethodCallExpression is equal to the return type of the method represented by method.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.