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Expression.Constant Method (Object)

Creates a ConstantExpression that has the Value property set to the specified value.

Namespace:  System.Linq.Expressions
Assembly:  System.Core (in System.Core.dll)
public static ConstantExpression Constant(
	Object value
)

Parameters

value
Type: System.Object

An Object to set the Value property equal to.

Return Value

Type: System.Linq.Expressions.ConstantExpression
A ConstantExpression that has the NodeType property equal to Constant and the Value property set to the specified value.

The Type property of the resulting ConstantExpression is equal to the type of value. If value is null, Type is equal to Object.

To represent null, you can also use the Constant(Object, Type) method, with which you can explicitly specify the type.

The following code example shows how to create an expression that represents a constant value.

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

// This expression represents a Constant value.
Expression constantExpr = Expression.Constant(5.5);

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

// You can also use variables. 
double num = 3.5;
constantExpr = Expression.Constant(num);
Console.WriteLine(constantExpr.ToString());

// This code example produces the following output: 
// 
// 5.5 
// 3.5

.NET Framework

Supported in: 4.5.1, 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 8, Silverlight 8.1

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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