This topic is included for completeness. For more detail see the source code located in the VC\atlmfc\src\mfc folder of your Visual Studio installation.
virtual int OnPaneDividerMove(
CPaneDivider* pSlider,
UINT uFlags,
int nOffset,
HDWP& hdwp
);
Parameters
[in] pSlider
[in] uFlags
[in] nOffset
[in] hdwp
Requirements
Header: afxpanecontainermanager.h