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LambdaExpression Class

Describes a lambda expression. This captures a block of code that is similar to a .NET method body.

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

public abstract class LambdaExpression : Expression

The LambdaExpression type exposes the following members.

  NameDescription
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsBodyGets the body of the lambda expression.
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsCanReduceIndicates 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 Portable Class LibrarySupported in .NET for Windows Store appsNameGets the name of the lambda expression.
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsNodeTypeReturns the node type of this Expression. (Overrides Expression.NodeType.)
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsParametersGets the parameters of the lambda expression.
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsReturnTypeGets the return type of the lambda expression.
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsTailCallGets the value that indicates if the lambda expression will be compiled with the tail call optimization.
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsTypeGets the static type of the expression that this Expression represents. (Overrides Expression.Type.)
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  NameDescription
Protected methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsAcceptDispatches to the specific visit method for this node type. For example, MethodCallExpression calls the VisitMethodCall. (Inherited from Expression.)
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsCompile()Produces a delegate that represents the lambda expression.
Public methodCompile(DebugInfoGenerator)Produces a delegate that represents the lambda expression.
Public methodCompileToMethod(MethodBuilder)Compiles the lambda into a method definition.
Public methodCompileToMethod(MethodBuilder, DebugInfoGenerator)Compiles the lambda into a method definition and custom debug information.
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsReduceReduces 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 methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsReduceAndCheckReduces 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 methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsReduceExtensionsReduces 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 Portable Class LibrarySupported in .NET for Windows Store appsToStringReturns a textual representation of the Expression. (Inherited from Expression.)
Protected methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsVisitChildrenReduces 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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The LambdaExpression type represents a lambda expression in the form of an expression tree. The Expression<TDelegate> type, which derives from LambdaExpression and captures the type of the lambda expression more explicitly, can also be used to represent a lambda expression. At runtime, an expression tree node that represents a lambda expression is always of type Expression<TDelegate>.

The value of the NodeType property of a LambdaExpression is Lambda.

Use the Lambda factory methods to create a LambdaExpression object.

The following example demonstrates how to create an expression that represents a lambda expression that adds 1 to the passed argument by using the Lambda method.

// Add the following directive to your file: 
// using System.Linq.Expressions;   

// A parameter for the lambda expression.
ParameterExpression paramExpr = Expression.Parameter(typeof(int), "arg");

// This expression represents a lambda expression 
// that adds 1 to the parameter value.
LambdaExpression lambdaExpr = Expression.Lambda(
    Expression.Add(
        paramExpr,
        Expression.Constant(1)
    ),
    new List<ParameterExpression>() { paramExpr }
);

// Print out the expression.
Console.WriteLine(lambdaExpr);

// Compile and run the lamda expression. 
// The value of the parameter is 1.
Console.WriteLine(lambdaExpr.Compile().DynamicInvoke(1));

// This code example produces the following output: 
// 
// arg => (arg +1) 
// 2

.NET Framework

Supported in: 4.5, 4, 3.5

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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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