Expression.Constant Method (Object, Type)
.NET Framework (current version)
Creates a ConstantExpression that has the Value and Type properties set to the specified values.
Assembly: System.Core (in System.Core.dll)
Return Value
Type: System.Linq.Expressions.ConstantExpressionA ConstantExpression that has the NodeType property equal to Constant and the Value and Type properties set to the specified values.
| Exception | Condition |
|---|---|
| ArgumentNullException | type is null. |
| ArgumentException | value is not null and type is not assignable from the dynamic type of value. |
This method can be useful for representing values of nullable types.
The following code example shows how to create an expression that represents a constant of the nullable type and set its value to null.
// Add the following directive to your file: // using System.Linq.Expressions; // This expression represents a constant value, // for which you can explicitly specify the type. // This can be used, for example, for defining constants of a nullable type. Expression constantExpr = Expression.Constant( null, typeof(double?) ); // Print out the expression. Console.WriteLine(constantExpr.ToString()); // This code example produces the following output: // // null
Universal Windows Platform
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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