Note
Access to this page requires authorization. You can try signing in or changing directories.
Access to this page requires authorization. You can try changing directories.
Although Automation allows you to implement an IDispatch interface, a VTBL interface, or a dual interface (which encompasses both), it is strongly recommended that you implement dual interfaces for all exposed ActiveX objects. Dual interfaces have significant advantages over IDispatch-only or VTBL-only interfaces.
Binding can take place at compile time through the VTBL interface, or at run time through IDispatch.
ActiveX clients that can use the VTBL interface may benefit from improved performance.
Existing ActiveX clients that use the IDispatch interface will continue to work.
The VTBL interface is easier to call from C++.
Dual interfaces are required for compatibility with Visual Basic object support features.