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MethodCallExpression Class

.NET Framework 4

Represents a call to either static or an instance method.

System.Object
  System.Linq.Expressions.Expression
    System.Linq.Expressions.MethodCallExpression

Namespace:  System.Linq.Expressions
Assembly:  System.Core (in System.Core.dll)
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public class MethodCallExpression : Expression

The MethodCallExpression type exposes the following members.

  Name Description
Public property Supported by Portable Class Library Arguments Gets a collection of expressions that represent arguments of the called method.
Public property 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.)
Public property Supported by Portable Class Library Method Gets the MethodInfo for the method to be called.
Public property NodeType Returns the node type of this Expression. (Overrides Expression.NodeType.)
Public property Supported by Portable Class Library Object Gets the Expression that represents the instance for instance method calls or null for static method calls.
Public property Type Gets the static type of the expression that this Expression represents. (Overrides Expression.Type.)
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  Name Description
Protected method Accept Dispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall. (Overrides Expression.Accept(ExpressionVisitor).)
Public method Supported by Portable Class Library Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected method Supported by Portable Class Library Finalize Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method Supported by Portable Class Library GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public method Supported by Portable Class Library GetType Gets the Type of the current instance. (Inherited from Object.)
Protected method Supported by Portable Class Library MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method 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.)
Public method 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.)
Public method 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.)
Public method Supported by Portable Class Library ToString Returns a textual representation of the Expression. (Inherited from Expression.)
Public method Update 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.
Protected method VisitChildren 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.)
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Use the Call, ArrayIndex, or ArrayIndex factory method to create a MethodCallExpression.

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

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

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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)

.NET Framework

Supported in: 4, 3.5

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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MethodCallExpression.Type
I don't think the explaination of MethodCallExpression.Type is correct, the Type here is the return type of the method represented by this expresion.

Edit by SJ at MSFT: I think I am missing your point. Could you give an example where the return type of the method and the static type of the expression are different? Thanks for clarifying.
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