RAD Studio VCL Reference
ContentsIndex
PreviousUpNext
Forms.THelpEvent Type

THelpEvent is the type of an OnHelp event handler.

Pascal
THelpEvent = function (Command: Word; Data: Longint; var CallHelp: Boolean): Boolean of object;
C++
(Command: Word; Data: Longint; var CallHelp: Boolean): Boolean ( THelpEvent)();

THelpEvent includes the following parameters: 

Command indicates the type of help command that was issued. It's meaning depends on the current help system. For example, when using WinHelp, Command is the command used by the WinHelp API. For details on possible commands, see the documentation provided by the developer of the application's help system. For example, if the application uses WinHelp, the possible commands are listed in the WinHelp section of the Win32 Developer's Reference. 

Data provides additional data to describe the desired action by the help system. Its value depends on the value of the Command property. Typically, Data specifies a keyword or context ID. For details, see the documentation provided by the application's help system. 

CallHelp is set by the event handler. If CallHelp is true when the event handler exits, the application should forward the help command to the help system. If the event handler handles the command, it sets CallHelp to false so that the application does not forward the help command to the help system. 

 

Copyright(C) 2009 Embarcadero Technologies, Inc. All Rights Reserved.
What do you think about this topic? Send feedback!