Signals that the user has clicked the Help button or pressed F1 for a control on a dialog.


#include "ltwrappr.h"

virtual L_VOID LScreenCapture::ScreenCaptureHelpCallBack(uFlag, nCtlID)


L_UINT32 uFlag

Flags that determine the options dialog that the Help button was clicked from. Possible values are:

Value Meaning
SCRDLG_HELP_SETCAPTUREOPTION [1] Help command message is coming from LScreenCapture::SetCaptureOptionDlg.
SCRDLG_HELP_CAPTUREAREAOPTION [2] Help command message is coming from LScreenCapture::CaptureAreaOptionDlg.
SCRDLG_HELP_CAPTUREOBJECTOPTION [3] Help command message is coming from LScreenCapture::CaptureObjectOptionDlg.
SCRDLG_HELP_CAPTUREFROMEXE [4] Help command message is coming from LScreenCapture::CaptureFromExeDlg.


ID of the control that received the context sensitive help click. A value of 1 refers to the help button itself. For a list of other possible values, refer to the LTSCR.H file in the C:\LEADTOOLS22\Include directory.


Value Meaning
SUCCESS The function was successful.
< 1 An error occurred. Refer to Return Codes.


This callback function is optional. It is necessary only if you wish to provide help information for individual dialogs. The exact nature of the help provided is up to you, but you must override this function in order to provide that help. In addition, you must call LBase::EnableCallBack before calling any function that uses this callback.

This callback function is used with the following methods:

Required DLLs and Libraries


Win32, x64.

See Also


For an example, refer to LScreenCapture::SetCaptureOptionDlg.

Help Version 22.0.2023.2.2
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