JVCL Help:TJvControlHook

 JVCL Help: TJvControlHook type

JVCL Types

► JvWndProcHook.pas Types

[+] JvWndProcHook.pas Types

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Summary

The type for a control hook procedure.

run\JvWndProcHook.pas

Pascal

 run\JvWndProcHook.pas

 TJvControlHook = function (var Msg: TMessage): Booleanofobject;

Parameters

Parameters	Description
Msg	Represents the Windows message send to the hooked control.

run\JvWndProcHook.pas

Description

TJvControlHook is the type for a control hook procedure that acts like a window procedure of a control. Like most window procedures, TJvControlHook takes a message record as an argument. The control hook should return true if it processes the message, and false if it does not. If the hook procedure is registered with parameter Order set to hoBeforeMsg, then returning true will prevent the hooked control to respond to the message.

run\JvWndProcHook.pas

See Also

RegisterWndProcHook, UnRegisterWndProcHook

run\JvWndProcHook.pas

About

Notes

Be careful with setting the result to true. For example, always returning true with a hook procedure that is registered with parameter Order set to hoBeforeMsg, will crash your application.

run\JvWndProcHook.pas

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