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SetScrollRange info  Overview  Group

The SetScrollRange function sets the minimum and maximum position values for the specified scroll bar.

The SetScrollRange function is provided for backward compatibility. New applications should use the SetScrollInfo function.

BOOL SetScrollRange(

    HWND hWnd,

// handle of window with scroll bar

    int nBar,

// scroll bar flag

    int nMinPos,

// minimum scrolling position

    int nMaxPos,

// maximum scrolling position

    BOOL bRedraw 

// redraw flag

   );

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 to be set. This parameter can be one of the following values:

Value

Meaning

SB_CTL

Sets the range of a scroll bar control. The hWnd parameter must be the handle of the scroll bar control.

SB_HORZ

Sets the range of a window’s standard horizontal scroll bar.

SB_VERT

Sets the range of a window’s standard vertical scroll bar.

nMinPos
Specifies the minimum scrolling position.
nMaxPos
Specifies the maximum scrolling position.
bRedraw
Specifies whether the scroll bar should be redrawn to reflect the change. If this parameter is TRUE, the scroll bar is redrawn. If it is FALSE, the scroll bar is not redrawn.

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

You can use SetScrollRange to hide the scroll bar by setting nMinPos and nMaxPos to the same value. An application should not call the SetScrollRange function to hide a scroll bar while processing a scroll bar message. New applications should use the ShowScrollBar function to hide the scroll bar.

If the call to SetScrollRange immediately follows a call to the SetScrollPos function, the bRedraw parameter in SetScrollPos must be zero to prevent the scroll bar from being drawn twice.

The default range for a standard scroll bar is 0 through 100. The default range for a scroll bar control is empty (both the nMinPos and nMaxPos parameter values are zero). The difference between the values specified by the nMinPos and nMaxPos parameters must not be greater than the value of MAXLONG.

Because the messages that indicate scroll bar position, WM_HSCROLL and WM_VSCROLL, are limited to 16 bits of position data, applications that rely solely on those messages for position data have a practical maximum value of 65,535 for the SetScrollRange function’s nMaxPos parameter.

However, because the SetScrollInfo, SetScrollPos, SetScrollRange, GetScrollInfo, GetScrollPos, and GetScrollRange functions support 32-bit scroll bar position data, there is a way to circumvent the 16-bit barrier of the WM_HSCROLL and WM_VSCROLL messages. See GetScrollInfo for a description of the technique.

See Also

GetScrollInfo, GetScrollPos, GetScrollRange, SetScrollInfo, SetScrollPos, ShowScrollBar