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InvocationExpression Class

 

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

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

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

public sealed class InvocationExpression : Expression, IArgumentProvider

NameDescription
System_CAPS_pubpropertyArguments

Gets the arguments that the delegate or lambda expression is applied to.

System_CAPS_pubpropertyCanReduce

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.)

System_CAPS_pubpropertyExpression

Gets the delegate or lambda expression to be applied.

System_CAPS_pubpropertyNodeType

Returns the node type of this expression. Extension nodes should return Extension when overriding this method.(Overrides Expression.NodeType.)

System_CAPS_pubpropertyType

Gets the static type of the expression that this Expression represents.(Overrides Expression.Type.)

NameDescription
System_CAPS_protmethodAccept(ExpressionVisitor)

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

System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethodReduce()

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.)

System_CAPS_pubmethodReduceAndCheck()

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.)

System_CAPS_pubmethodReduceExtensions()

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.)

System_CAPS_pubmethodToString()

Returns a textual representation of the Expression.(Inherited from Expression.)

System_CAPS_pubmethodUpdate(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.

System_CAPS_protmethodVisitChildren(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.)

NameDescription
System_CAPS_pubinterfaceSystem_CAPS_privmethodIArgumentProvider.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.

System_CAPS_pubinterfaceSystem_CAPS_privpropertyIArgumentProvider.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.

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));

Console.WriteLine(invocationExpression.ToString());

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

Universal Windows Platform
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1

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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