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Expression.New Method (Type)

Creates a NewExpression that represents calling the parameterless constructor of the specified type.

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

'Declaration
Public Shared Function New ( _
	type As Type _
) As NewExpression

Parameters

type
Type: System.Type

A Type that has a constructor that takes no arguments.

Return Value

Type: System.Linq.Expressions.NewExpression
A NewExpression that has the NodeType property equal to New and the Constructor property set to the ConstructorInfo that represents the constructor without parameters for the specified type.

ExceptionCondition
ArgumentNullException

type is Nothing.

ArgumentException

The type that type represents does not have a constructor without parameters.

The type parameter must represent a type that has a constructor without parameters.

The Arguments and Members properties of the resulting NewExpression are empty collections. The Type property is equal to type.

The following example demonstrates how to use the New(Type) method to create a NewExpression that represents constructing a new instance of a dictionary object by calling the constructor without parameters.

' Create a NewExpression that represents constructing 
' a new instance of Dictionary(Of Integer, String). 
Dim newDictionaryExpression As System.Linq.Expressions.NewExpression = _
    System.Linq.Expressions.Expression.[New]( _
        Type.GetType("System.Collections.Generic.Dictionary`2[System.Int32, System.String]"))

Console.WriteLine(newDictionaryExpression.ToString())

' This code produces the following output: 

' new Dictionary`2()

.NET Framework

Supported in: 4.6, 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

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: 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.

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