OptionalAttribute Class
Indicates that a parameter is optional.
For a list of all members of this type, see OptionalAttribute Members.
System.Object
System.Attribute
System.Runtime.InteropServices.OptionalAttribute
[Visual Basic] <AttributeUsage(AttributeTargets.Parameter)> NotInheritable Public Class OptionalAttribute Inherits Attribute [C#] [AttributeUsage(AttributeTargets.Parameter)] public sealed class OptionalAttribute : Attribute [C++] [AttributeUsage(AttributeTargets::Parameter)] public __gc __sealed class OptionalAttribute : public Attribute [JScript] public AttributeUsage(AttributeTargets.Parameter) class OptionalAttribute extends Attribute
Thread Safety
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Remarks
You can apply this attribute to parameters.
Optional parameters are not supported by all languages.
Requirements
Namespace: System.Runtime.InteropServices
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family
Assembly: Mscorlib (in Mscorlib.dll)
See Also
OptionalAttribute Members | System.Runtime.InteropServices Namespace