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Expression.Default Method

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

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

public static DefaultExpression Default(
	Type type
)

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: 
// using System.Linq.Expressions;   

// This expression represents the default value of a type 
// (0 for integer, null for a string, etc.)
Expression defaultExpr = Expression.Default(
                            typeof(byte)
                        );

// Print out the expression.
Console.WriteLine(defaultExpr.ToString());

// The following statement first creates an expression tree, 
// then compiles it, and then executes it.
Console.WriteLine(
    Expression.Lambda<Func<byte>>(defaultExpr).Compile()());

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

.NET Framework

Supported in: 4.5, 4

.NET Framework Client Profile

Supported in: 4

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.

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