WinIsRectEmpty: Difference between revisions
Created page with "This function ''checks whether a rectangle is empty''. ==Syntax== WinIsRectEmpty(hab, prclprc) ==Parameters== ;hab (HAB) - Input : Anchor-block handle. ;prclprc (PRECTL) - Input : Rectangle to be checked. :;Note :: The value of each field in this structure must be in the range -32 768 through 32 767. The data type WRECT can also be used, if supported by the language. ==Returns== ;rc (BOOL) - returns : Empty indicator. :;TRUE :: Rectangle is empty :;FA..." |
|||
| Line 56: | Line 56: | ||
* [[WinInflateRect]] | * [[WinInflateRect]] | ||
* [[WinIntersectRect]] | * [[WinIntersectRect]] | ||
* [[WinOffsetRect]] | * [[WinOffsetRect]] | ||
* [[WinPtInRect]] | * [[WinPtInRect]] | ||
Latest revision as of 03:10, 9 April 2025
This function checks whether a rectangle is empty.
Syntax
WinIsRectEmpty(hab, prclprc)
Parameters
- hab (HAB) - Input
- Anchor-block handle.
- prclprc (PRECTL) - Input
- Rectangle to be checked.
- Note
- The value of each field in this structure must be in the range -32 768 through 32 767. The data type WRECT can also be used, if supported by the language.
Returns
- rc (BOOL) - returns
- Empty indicator.
- TRUE
- Rectangle is empty
- FALSE
- Rectangle is not empty
Remarks
A rectangle has area if its left edge coordinate is less than its right edge coordinate, and its bottom edge coordinate is less than its top edge coordinate. An empty rectangle is one with no area.
Errors
Possible returns from WinGetLastError: (No specific errors were listed in the provided text.)
Example Code
#define INCL_WINRECTANGLES /* Or use INCL_WIN, INCL_PM, */ #include <os2.h> HAB hab; /* Anchor-block handle. */ PRECTL prclprc; /* Rectangle to be checked. */ BOOL rc; /* Empty indicator. */ rc = WinIsRectEmpty(hab, prclprc);
This example checks if a rectangle is empty (i.e. it has no area).
#define INCL_WINRECTANGLES /* Window Rectangle Functions */
#include <os2.h>
BOOL fEmpty; /* empty indicator */
HAB hab; /* anchor-block handle */
RECTL prclRect1 = {0,0,100,100}; /* rectangle */
fEmpty = WinIsRectEmpty(hab, &prclRect1);