The ComClassAttribute attribute instructs the compiler to add meta-data that allows a class to be exposed as a COM object.
<System.AttributeUsage(System.AttributeTargets.Class, _ Inherited := False, AllowMultiple := False)> _ Public NotInheritable Class ComClassAttribute Inherits System.Attribute
Use ComClassAttribute to simplify the process of creating COM components from Visual Basic .NET. COM objects are considerably different from .NET assemblies, and without the ComClassAttribute, you need to follow a number of steps to generate a COM object from Visual Basic .NET. For classes marked with ComClassAttribute, the compiler performs many of these steps automatically.
To run this example, create a new Class Library application and add the following code to a class module.
<ComClass(ComClass1.ClassId, ComClass1.InterfaceId, ComClass1.EventsId)> _ Public Class ComClass1 ' Use the Region directive to define a section named COM Guids. #Region "COM GUIDs" ' These GUIDs provide the COM identity for this class ' and its COM interfaces. You can generate ' these guids using guidgen.exe Public Const ClassId As String = "7666AC25-855F-4534-BC55-27BF09D49D46" Public Const InterfaceId As String = "54388137-8A76-491e-AA3A-853E23AC1217" Public Const EventsId As String = "EA329A13-16A0-478d-B41F-47583A761FF2" #End Region Public Sub New() MyBase.New() End Sub Function AddNumbers(ByVal X As Integer, ByVal Y As Integer) AddNumbers = X + Y End Function End Class