Default Method
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Expression.Default Method

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

Creates a DefaultExpression that has the Type property set to the specified type.

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

'Declaration
Public Shared Function Default ( _
	type As Type _
) As DefaultExpression

Parameters

type
Type: System.Type
A Type to set the Type property equal to.

Return Value

Type: System.Linq.Expressions.DefaultExpression
A DefaultExpression that has the NodeType property equal to Default and the Type property set to the specified type.

The following code example shows how to create an expression that represents a default vaule for a given type.


' Add the following directive to your file:
' Imports System.Linq.Expressions  

' This expression represents the default value of a type
' (0 for integer, null for a string, and so on).
Dim defaultExpr As Expression = Expression.Default(
                                        GetType(Byte)
                                    )

' Print the expression.
outputBlock.Text &= defaultExpr.ToString() & vbCrLf

' The following statement first creates an expression tree,
' then compiles it, and then executes it.
outputBlock.Text &=
    Expression.Lambda(Of Func(Of Byte))(defaultExpr).Compile()() & vbCrLf

' This code example produces the following output:
'
' default(Byte)
' 0


Windows Phone OS

Supported in: 8.1, 8.0

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