An application sends the SBM_GETSCROLLINFO message to set the parameters of a scroll bar.
SBM_SETSCROLLINFO wParam = (WPARAM) fRedraw; // redraw flag lParam = (LPARAM) (LPSCROLLINFO) lpsi; // scroll bar parameters
The fMask member can be a combination of the following values:
Value |
Meaning |
SIF_DISABLENOSCROLL |
Disables the scroll bar instead of removing it, if the scroll bar’s new parameters make the scroll bar unnecessary. |
SIF_PAGE |
Sets the scroll page to the value specified in the nPage member of the SCROLLINFO structure pointed to by lpsi. |
SIF_POS |
Sets the scroll position to the value specified in the nPos member of the SCROLLINFO structure pointed to by lpsi. |
SIF_RANGE |
Sets the scroll range to the value specified in the nMin and nMax members of the SCROLLINFO structure pointed to by lpsi. |
The return value is the current position of the scroll box.
The messages that indicate scroll-bar position, WM_HSCROLL and WM_VSCROLL, provide only 16 bits of position data. However, the SCROLLINFO structure used by SBM_GETSCROLLINFO, SBM_SETSCROLLINFO, GetScrollInfo, and SetScrollInfo provides 32 bits of scroll-bar position data. You can use these messages and functions while processing either the WM_HSCROLL or WM_VSCROLL messages to obtain 32-bit scroll-bar position data.