Expression.Lambda(TDelegate) Method (Expression, ParameterExpression[]) (System.Linq.Expressions)

Lambda(TDelegate) Method (Expressio...

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Microsoft Visual Studio 2008/.NET Framework 3.5

Other versions are also available for the following:

.NET Framework Class Library

Expression..::.Lambda<(Of <(TDelegate>)>) Method (Expression, array<ParameterExpression>[]()[])

Creates an Expression<(Of <(TDelegate>)>) where the delegate type is known at compile time.

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

Syntax

Visual Basic (Declaration)

Public Shared Function Lambda(Of TDelegate) ( _
    body As Expression, _
    ParamArray parameters As ParameterExpression() _
) As Expression(Of TDelegate)

Visual Basic (Usage)

Dim body As Expression
Dim parameters As ParameterExpression()
Dim returnValue As Expression(Of TDelegate)

returnValue = Expression.Lambda(body, parameters)

public static Expression<TDelegate> Lambda<TDelegate>(
    Expression body,
    params ParameterExpression[] parameters
)

Visual C++

public:
generic<typename TDelegate>
static Expression<TDelegate>^ Lambda(
    Expression^ body, 
    ... array<ParameterExpression^>^ parameters
)

JScript

JScript does not support generic types or methods.

Type Parameters

TDelegate: A delegate type.

Parameters

body: Type: System.Linq.Expressions..::.Expression
An Expression to set the Body property equal to.

parameters: Type: array<System.Linq.Expressions..::.ParameterExpression>[]()[]
An array of ParameterExpression objects to use to populate the Parameters collection.

Return Value

Type: System.Linq.Expressions..::.Expression<(Of <(TDelegate>)>)
An Expression<(Of <(TDelegate>)>) that has the NodeType property equal to Lambda and the Body and Parameters properties set to the specified values.

Exceptions

Exception	Condition
ArgumentNullException	body is nullNothingnullptra null reference (Nothing in Visual Basic). -or- One or more elements in parameters are nullNothingnullptra null reference (Nothing in Visual Basic).
ArgumentException	TDelegate is not a delegate type. -or- body.Type represents a type that is not assignable to the return type of TDelegate. -or- parameters does not contain the same number of elements as the list of parameters for TDelegate. -or- The Type property of an element of parameters is not assignable from the type of the corresponding parameter type of TDelegate.

Exception

Condition

ArgumentNullException

body is nullNothingnullptra null reference (Nothing in Visual Basic).

-or-

One or more elements in parameters are nullNothingnullptra null reference (Nothing in Visual Basic).

ArgumentException

TDelegate is not a delegate type.

-or-

body.Type represents a type that is not assignable to the return type of TDelegate.

-or-

parameters does not contain the same number of elements as the list of parameters for TDelegate.

-or-

The Type property of an element of parameters is not assignable from the type of the corresponding parameter type of TDelegate.

Remarks

The number of parameters for the delegate type TDelegate must equal the number of elements in parameters.

The elements of parameters must be reference equal to the parameter expressions in body.

The Type property of the resulting object represents the type TDelegate. If parameters is nullNothingnullptra null reference (Nothing in Visual Basic), the Parameters property of the resulting object is an empty collection.

Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Version Information

.NET Framework

Supported in: 3.5

Reference

Expression Class

Expression Members

Lambda Overload

System.Linq.Expressions Namespace