Retrieving Objects
Automation provides several functions to identify and retrieve the active instance of an object or application, so you can make the object available to others.
RegisterActiveObject — Sets the active object for an application. Use when the application starts.
RevokeActiveObject — Revokes the active object. Use when the application ends.
GetActiveObject — Retrieves a pointer to the active object. In Visual Basic, this pointer is implemented by the GetObject function.
Applications can have more than one active object at a time. To be initialized as active, an object must:
Have a class factory (that is, the object provides an interface for creating instances of itself).
Identify its class factory by a ProgID in the system registry.
Be registered by a call to RegisterActiveObject when the object is created, or when it becomes active.
The Application object must be registered as an active object.