Core.DefaultValueAttribute Class (F#)
Adding this attribute to a field declaration means that the field is not initialized. During type checking a constraint is asserted that the field type supports null. If the Check value is false then the constraint is not asserted.
Namespace/Module Path: Microsoft.FSharp.Core
Assembly: FSharp.Core (in FSharp.Core.dll)
[<AttributeUsage(AttributeTargets.Field, AllowMultiple = false)>]
[<Sealed>]
type DefaultValueAttribute =
class
new DefaultValueAttribute : bool -> DefaultValueAttribute
new DefaultValueAttribute : unit -> DefaultValueAttribute
member this.Check : bool
end
Remarks
This attribute is intended to be used on explicit fields in classes and structures. It shouldn't be used on records. For more information, see Records (F#) and Explicit Fields: The val Keyword (F#).
The .NET Framework namespace System.ComponentModel defines an attribute that has the same name: DefaultValueAttribute. Therefore, you must fully qualify the F# attribute if you open the System.ComponentModel namespace.
You can also use the short form of the name, DefaultValue.
Constructors
Member |
Description |
---|---|
Creates an instance of the attribute |
Instance Members
Member |
Description |
---|---|
Indicates if a constraint is asserted that the field type supports 'null' |
Platforms
Windows 8, Windows 7, Windows Server 2012, Windows Server 2008 R2
Version Information
F# Core Library Versions
Supported in: 2.0, 4.0, Portable