EnumDisplaySettings
The EnumDisplaySettings
function obtains information about one of a display device s graphics modes.
You can obtain information for all of a display device s graphics modes by
making a series of calls to this function.
BOOL EnumDisplaySettings(
LPCTSTR lpszDeviceName, |
// specifies the
display device |
DWORD iModeNum, |
// specifies the
graphics mode |
LPDEVMODE lpDevMode |
// points to
structure to receive settings |
); |
|
Parameters
lpszDeviceName
Pointer to a
null-terminated string that specifies the display device whose graphics mode
the function will obtain information about.
This
parameter can be NULL. A NULL value specifies the current display device on the
computer that the calling thread is running on.
If lpszDeviceName
is not NULL, the string must be of the form \\.\DisplayX, where X
can have the values 1, 2, or 3.
Windows
95: lpszDeviceName must be
NULL.
iModeNum
Index value
that specifies the graphics mode for which information is to be obtained.
Graphics mode
indexes start at zero. To obtain information for all of a display device s
graphics modes, make a series of calls to EnumDisplaySettings, as
follows: Set iModeNum to zero for the first call, and increment iModeNum
by one for each subsequent call. Continue calling the function until the return
value is FALSE.
When you call
EnumDisplaySettings with iModeNum set to zero, the operating
system initializes and caches information about the display device. When you
call EnumDisplaySettings with iModeNum set to a non-zero value,
the function returns the information that was cached the last time the function
was called with iModeNum set to zero.
lpDevMode
Pointer to a DEVMODE
The EnumDisplaySettings
function sets values for the following five DEVMODE members:
dmBitsPerPel
dmPelsWidth
dmPelsHeight
dmDisplayFlags
dmDisplayFrequency
Return Values
If the
function succeeds, the return value is nonzero.
If the
function fails, the return value is zero.
The function
fails if iModeNum is greater than the index of the display device s last
graphics mode. As noted in the description of the iModeNum parameter,
you can use this behavior to enumerate all of a display device s graphics
modes.
See Also