System.TObject.Dispatch
Delphi
procedure Dispatch(var Message); virtual;
C++
virtual void __fastcall Dispatch(void *Message);
Properties
Type | Visibility | Source | Unit | Parent |
---|---|---|---|---|
procedure function |
public | System.pas systobj.h |
System | TObject |
Description
Calls message-handling methods for the object, based on the contents of the Message parameter.
Call Dispatch to automatically pass messages to the appropriate message handler.
Dispatch determines whether a message is in the list of message handlers declared for the object. If the object does not handle the message, Dispatch then examines the message-handler list of the ancestor class, and continues checking ancestors until it either finds a specific handler or runs out of ancestors, in which case it calls DefaultHandler.
The only assumption Dispatch makes about the data in Message is that the first two bytes contain a message ID—that is, an integer that determines which message handler Dispatch calls. Although any kind of data can be passed to Dispatch, most TObject descendants expect a message record such as TMessage or a specific data structure type.
See Also
Code Examples