IUnknownConstantAttribute Class

Reference

Definition

Namespace:: System.Runtime.CompilerServices

Assembly:: System.Runtime.InteropServices.dll

Assembly:: mscorlib.dll

Assembly:: netstandard.dll

Source:: IUnknownConstantAttribute.cs

Source:: IUnknownConstantAttribute.cs

Source:: IUnknownConstantAttribute.cs

Important

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Indicates that the default value for the attributed field or parameter is an instance of UnknownWrapper, where the WrappedObject is null. This class cannot be inherited.

public ref class IUnknownConstantAttribute sealed : System::Runtime::CompilerServices::CustomConstantAttribute

[System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter, Inherited=false)]
public sealed class IUnknownConstantAttribute : System.Runtime.CompilerServices.CustomConstantAttribute

[System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter, Inherited=false)]
[System.Serializable]
public sealed class IUnknownConstantAttribute : System.Runtime.CompilerServices.CustomConstantAttribute

[System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter, Inherited=false)]
[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class IUnknownConstantAttribute : System.Runtime.CompilerServices.CustomConstantAttribute

[<System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter, Inherited=false)>]
type IUnknownConstantAttribute = class
    inherit CustomConstantAttribute

[<System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter, Inherited=false)>]
[<System.Serializable>]
type IUnknownConstantAttribute = class
    inherit CustomConstantAttribute

[<System.AttributeUsage(System.AttributeTargets.Field | System.AttributeTargets.Parameter, Inherited=false)>]
[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type IUnknownConstantAttribute = class
    inherit CustomConstantAttribute

Public NotInheritable Class IUnknownConstantAttribute
Inherits CustomConstantAttribute

Inheritance: Object

Attribute

CustomConstantAttribute
IUnknownConstantAttribute

Attributes: AttributeUsageAttribute SerializableAttribute ComVisibleAttribute

Remarks

You can apply this attribute to fields or parameters.

The type library importer uses this attribute to distinguish a default value of type VT_UNKNOWN from null.

For more information about constant attributes, see the CustomConstantAttribute class.

The classes in System.Runtime.CompilerServices are for compiler writers use only.

Constructors

IUnknownConstantAttribute()

Initializes a new instance of the IUnknownConstantAttribute class.

Properties

TypeId	When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute)
Value	Gets the `IUnknown` constant stored in this attribute.

Methods

Equals(Object)	Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute)
GetHashCode()	Returns the hash code for this instance. (Inherited from Attribute)
GetType()	Gets the Type of the current instance. (Inherited from Object)
IsDefaultAttribute()	When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute)
Match(Object)	When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)

Explicit Interface Implementations

_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)	Maps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute)
_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)	Retrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute)
_Attribute.GetTypeInfoCount(UInt32)	Retrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)	Provides access to properties and methods exposed by an object. (Inherited from Attribute)

Applies to

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