The TVbxEventHandler class is quite small and, for the most part, of little interest to most programmers.

What it does is very important, though. Without the functionality contained in this class, you could not communicate with your VBX controls. The event-handling programming model is described in greater detail in Handling VBX Control Messages; this topic explains only the part that TVbxEventHandler plays in the process.

TVbxEventHandler consists of a single function and a one-message response table. The function, called TVbxEventHandler::EvVbxDispatch, is the event-handling routine for a message called WM_VBXFIREEVENT. EvVbxDispatch receives the WM_VBXFIREEVENT message, converts the uncracked message to a VBXEVENT structure, and dispatches a new message, which is handled by the control's parent. Because the parent object is necessarily derived from TVbxEventHandler, the parent calls back to itself with a different message. The new message is much easier to handle and understand. This is the message that is handled by the EV_VBXEVENTNAME macro.

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