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InvocationExpression Class

Represents an expression that applies a delegate or lambda expression to a list of argument expressions.

System.Object
  System.Linq.Expressions.Expression
    System.Linq.Expressions.InvocationExpression

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

public sealed class InvocationExpression : Expression

The InvocationExpression type exposes the following members.

  NameDescription
Public propertySupported by Silverlight for Windows PhoneArgumentsGets the arguments that the delegate or lambda expression is applied to.
Public propertyCanReduceIndicates 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 propertySupported by Silverlight for Windows PhoneExpressionGets the delegate or lambda expression to be applied.
Public propertySupported by Silverlight for Windows PhoneNodeTypeReturns the node type of this expression. Extension nodes should return Extension when overriding this method. (Overrides Expression.NodeType.)

In Silverlight for Windows Phone Windows Phone OS 7.1, this member is inherited from Expression.NodeType.


In XNA Framework Windows Phone OS 7.0, this member is inherited from Expression.NodeType.
Public propertySupported by Silverlight for Windows PhoneTypeGets the static type of the expression that this Expression represents. (Overrides Expression.Type.)

In Silverlight for Windows Phone Windows Phone OS 7.1, this member is inherited from Expression.Type.


In XNA Framework Windows Phone OS 7.0, this member is inherited from Expression.Type.
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  NameDescription
Protected methodAcceptDispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall. (Inherited from Expression.)
Public methodSupported by Silverlight for Windows PhoneEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodSupported by Silverlight for Windows PhoneFinalizeAllows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public methodSupported by Silverlight for Windows PhoneGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodSupported by Silverlight for Windows PhoneGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodSupported by Silverlight for Windows PhoneMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodReduceReduces 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 methodReduceAndCheckReduces 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 methodReduceExtensionsReduces 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 methodSupported by Silverlight for Windows PhoneToStringReturns a textual representation of the Expression. (Inherited from Expression.)
Public methodUpdateCreates 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 methodVisitChildrenReduces 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 Invoke factory methods to create an InvocationExpression.

The NodeType of an InvocationExpression is Invoke.

The following example creates an InvocationExpression that represents invoking a lambda expression with specified arguments.


System.Linq.Expressions.Expression<Func<int, int, bool>> largeSumTest =
    (num1, num2) => (num1 + num2) > 1000;

// Create an InvocationExpression that represents applying
// the arguments '539' and '281' to the lambda expression 'largeSumTest'.
System.Linq.Expressions.InvocationExpression invocationExpression =
    System.Linq.Expressions.Expression.Invoke(
        largeSumTest,
        System.Linq.Expressions.Expression.Constant(539),
        System.Linq.Expressions.Expression.Constant(281));

outputBlock.Text += invocationExpression.ToString() + "\n";

// This code produces the following output:
//
// Invoke((num1, num2) => ((num1 + num2) > 1000),539,281)


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

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

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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