EnumDisplaySettings (Compact 2013)

3/28/2014

This function retrieves information about one of the graphics modes for a display device. To retrieve information for all the graphics modes of a display device, make a series of calls to this function.

Syntax

BOOL EnumDisplaySettings(
  LPCTSTR lpszDeviceName,
  DWORD iModeNum,
  LPDEVMODE lpDevMode
);

Parameters

• lpszDeviceName
  [in] Pointer to a null-terminated string that specifies the display device.

  This parameter is either NULL or a DISPLAY_DEVICE.DeviceName returned from EnumDisplayDevices.

  A NULL value specifies the current display device on the system that is running the calling thread.

• iModeNum
  [in] Specifies the type of information to retrieve.

  This value can be a graphics mode index or one of values shown in the following table.

  Value	Description
  ENUM_CURRENT_SETTINGS	Retrieve the current settings for the display device.
  ENUM_REGISTRY_SETTINGS	Retrieve the settings for the display devices that are currently stored in the registry.

  For more information, see Remarks.

• lpDevMode
  [out] Pointer to a DEVMODE structure that will contain the information about the specified graphics mode.

  Before calling EnumDisplaySettings, set the dmSize member to sizeof(DEVMODE), and set the dmDriverExtra member to indicate the size, in bytes, of the additional space available to receive private driver data.

  The EnumDisplaySettings function sets values for the following DEVMODE members:

  • dmBitsPerPel
  • dmPelsWidth
  • dmPelsHeight
  • dmDisplayFlags
  • dmDisplayFrequency

Return Value

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

The function fails if iModeNum is greater than the index of the display device's last graphics mode.

You can use iModeNum to enumerate all of a display device's graphics modes.

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. To do this, set iModeNum to zero for the first call and then increment iModeNum by one for each subsequent call. Continue calling the function until the return value is zero.

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 nonzero value, the function returns the information that was cached the last time the function was called with iModeNum set to zero.

Requirements

See Also

Reference

GDI Functions
ChangeDisplaySettingsEx
CreateDC
DEVMODE
DISPLAY_DEVICE
EnumDisplayDevices