GetScrollRange

GetScrollRange

The GetScrollRange function retrieves the current minimum and maximum scroll box (thumb) positions for the specified scroll bar.

For Windows 95, the GetScrollRange function exists for compatibility with operating system versions earlier than 4.0. With version 4.0 or later, use the GetScrollInfo function.

BOOL GetScrollRange(

HWND hWnd,	// handle of window with scroll bar
int nBar,	// scroll bar flags
LPINT lpMinPos,	// address of variable that receives minimum position
LPINT lpMaxPos	// address of variable that receives maximum position
);

Parameters

hWnd

Identifies a scroll bar control or a window with a standard scroll bar, depending on the value of the nBar parameter.

nBar

Specifies the scroll bar from which the positions are retrieved. This parameter can be one of the following values:

Value	Meaning
SB_CTL	Retrieves the positions of a scroll bar control. The hWnd parameter must be the handle of the scroll bar control.
SB_HORZ	Retrieves the positions of the window's standard horizontal scroll bar.
SB_VERT	Retrieves the positions of the window's standard vertical scroll bar.

lpMinPos

Points to the integer variable that receives the minimum position.

lpMaxPos

Points to the integer variable that receives the maximum position.

Return Values

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

Remarks

If the specified window does not have standard scroll bars or is not a scroll bar control, the GetScrollRange function copies zero to the lpMinPos and lpMaxPos parameters.

The default range for a standard scroll bar is 0 through 100. The default range for a scroll bar control is empty (both values are zero).

The messages that indicate scroll bar position, WM_HSCROLL and WM_VSCROLL, are limited to 16 bits of position data. However, because SetScrollPos, SetScrollRange, GetScrollPos, and GetScrollRange support 32-bit scroll bar position data, there is a way to circumvent the 16-bit barrier for the WM_HSCROLL and WM_VSCROLL messages. See the GetScrollPos function for a description of the technique and its limits.