ComEventInterfaceAttribute Class



This API is now obsolete.

Identifies the source interface and the class that implements the methods of the event interface that is generated when a coclass is imported from a COM type library.

public ref class ComEventInterfaceAttribute sealed : Attribute
[System.AttributeUsage(System.AttributeTargets.Interface, Inherited=false)]
[System.Obsolete("ComEventInterfaceAttribute may be unavailable in future releases.")]
public sealed class ComEventInterfaceAttribute : Attribute
type ComEventInterfaceAttribute = class
    inherit Attribute
Public NotInheritable Class ComEventInterfaceAttribute
Inherits Attribute


You can apply this attribute to interfaces, although the Tlbimp.exe (Type Library Importer) typically applies it for you when it imports a type library.

When a source interface is imported from a type library, any methods it implements are added as events to a generated event interface. Tlbimp.exe applies ComEventInterfaceAttribute to the event interface to identify the managed class that implements the methods of the event interface and implements the original source interface. The common language runtime uses this attribute at run time to perform the following tasks:

  • Associate events exposed by the interface to their implementation in the event provider class.

  • Link the events to the original COM source interface.

You rarely apply this attribute. However, if you plan to write source code that produces metadata that closely simulates metadata produced by Tlbimp.exe, you should create a event interface for each original source interface. For a detailed description about how Tlbimp.exe imports events, see Imported Member Conversion. For instruction about how to expose a COM event to a .NET client, see How to: Handle Events Raised by a COM Source.


ComEventInterfaceAttribute(Type, Type)

Initializes a new instance of the ComEventInterfaceAttribute class with the source interface and event provider class.



Gets the class that implements the methods of the event interface.


Gets the original source interface from the type library.


When implemented in a derived class, gets a unique identifier for this Attribute.

(Inherited from Attribute)



Returns a value that indicates whether this instance is equal to a specified object.

(Inherited from Attribute)

Returns the hash code for this instance.

(Inherited from Attribute)

Gets the Type of the current instance.

(Inherited from Object)

When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.

(Inherited from Attribute)

When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.

(Inherited from Attribute)

Creates a shallow copy of the current Object.

(Inherited from Object)

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)

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

See also