|
Overview |
|
|
|
Group |
|
|
|
Quick Info
Windows NT
| Yes
| Win95
| Yes
| Win32s
| No
| Import Library
| user32.lib
| Header File
| winuser.h
| Unicode
| WinNT
| Platform Notes
| None
|
|
|
ChangeDisplaySettings
The ChangeDisplaySettings function changes the display settings to the specified graphics mode.
LONG ChangeDisplaySettings(
LPDEVMODE lpDevMode,
|
| DWORD dwflags
|
| );
|
|
Parameters
lpDevMode
Pointer to a DEVMODE structure that describes the graphics mode to switch to. The dmSize member must be initialized to the size, in bytes, of the DEVMODE structure. The following fields in the DEVMODE structure are used:
Member
| Meaning
| dmBitsPerPel
| Bits per pixel
| dmPelsWidth
| Pixel width
| dmPelsHeight
| Pixel height
| dmDisplayFlags
| Mode flags
| dmDisplayFrequency
| Mode frequency
|
In addition to setting a value in one or more of the preceding DEVMODE members, you must also set the appropriate flags in the dmFields member. The flags indicate which members of the DEVMODE structure are used for the display settings change. If the appropriate bit is
not set in dmFields, the display setting will not be changed. Set one or more of the following
flags:
Flag
| Meaning
| DM_BITSPERPEL
| Use the dmBitsPerPel value.
| DM_PELSWIDTH
| Use the dmPelsWidth value.
| DM_PELSHEIGHT
| Use the dmPelsHeight value.
| DM_DISPLAYFLAGS
| Use the dmDisplayFlags value.
| DM_DISPLAYFREQENCY
| Use the dmDisplayFrequency value.
|
If lpDevMode is NULL, all the values currently in the registry will be used for the
display setting. Passing NULL for the lpDevMode parameter is the easiest way to return to the default mode after a dynamic
mode change.
dwflags
Indicates how the graphics mode should be changed. May be one of the following:
Flag
| Meaning
| 0
| The graphics mode for the current screen will be changed dynamically.
| CDS_UPDATEREGISTRY
| The graphics mode for the current screen will be changed dynamically and the
graphics mode will be updated in the registry. The mode information is stored in
the USER profile.
| CDS_TEST
| The system tests if the requested graphics mode could be set.
|
If CDS_UPDATEREGISTRY is specified and it is possible to change the graphics
mode dynamically, the information is stored in the registry and
DISP_CHANGE_SUCCESSFUL is returned. If it is not possible to change the graphics mode
dynamically, the information is stored in the registry and DISP_CHANGE_RESTART is
returned.
Windows NT: If the information could not be stored in the registry, the graphics mode is
not changed and DISP_CHANGE_NOTUPDATED is returned.
Specifying CDS_TEST allows an application to determine which graphics modes
are actually valid, without causing the system to change to that graphics mode.
Return Values
Returns one of the following values:
Value
| Meaning
| DISP_CHANGE_SUCCESSFUL
| The settings change was successful.
| DISP_CHANGE_RESTART
| The computer must be restarted in order for the graphics mode to work.
| DISP_CHANGE_BADFLAGS
| An invalid set of flags was passed in.
| DISP_CHANGE_FAILED
| The display driver failed the specified graphics mode.
| DISP_CHANGE_BADMODE
| The graphics mode is not supported.
| DISP_CHANGE_NOTUPDATED
| Windows NT only: Unable to write settings to the registry.
|
Remarks
Using the DEVMODE returned by the EnumDisplaySettings function ensures that the DEVMODE passed to ChangeDisplaySettings is valid and contains only values supported by the display driver.
When the display mode is changed dynamically, the WM_DISPLAYCHANGE message is
sent to all running applications with the following message parameters:
Parameters
| Meaning
| wParam
| New bits per pixel
| LOWORD(lParam)
| New pixel width
| HIWORD(lParam)
| New pixel height
|
See Also
CreateDC, DEVMODE, EnumDisplaySettings, WM_DISPLAYCHANGE
| Last news from Greatis Software |
 |
|
Nostalgia .Net |
|
.Net is powerful, but not all-powerful, so sometimes we need to use Win32 API for our .Net applications. It's simple enough with Platform Invoke if you have Win32 skill, but we do not always have time to dig the ancient documentation, declare the special types that are compatible with Win32, find the values of the Win32's constants and so on. Nostalgia .Net offers several simple-to-use classes, and components that will allow you to forget about the headache of Win32 and just use the power of Win32 in your application the same way as you use the native. Net classes. More » |
| Recommended software for developers |
 |
|
Ultimate Pack |
|
Component pack for Delphi and C++ Builder that contains runtime form designer, runtime object inspector, print suite and much more for the very special price. More » |
 |
|
Form Designer .Net |
|
Unique runtime form design solution that allows to edit any form in .Net WinForms application at runtime with full source codes for only 300 euro! More » |
 |
|
Print Suite .Net |
|
Print Suite .Net is a set of components for easy printing texts, images and grids from your WinForms applications. Full C# source codes are available More » |
 |
|
Gradient Controls .Net |
|
Gradient Controls .Net offers controls with gradient background feature. Labels, panels and so on... Full C# source codes are available More » |
 |
|
Greatis iGrid |
|
iGrid plots drawing grid right over your desktop, so you can use it everywhere, with any drawing application without any special plugins for different graphic editors. More » |
All the contacts and projectsDmitry Vasiliev (just.dmitry)
Related LinksSoftware for Visual Studio .NET developers
Software for Delphi and C++ Builder developers
Software for Visual Basic 6 developers
Delphi Tips&Tricks
MegaDetailed.NET More Online Helps Win32 Programmer's Reference
Win32 Multimedia Programmer's Reference
OLE Programmer's Reference
Microsoft Windows Pen API Programmer's Reference
Microsoft Windows Sockets 2 Reference
Microsoft Windows Telephony API (TAPI) Programmer's Reference
Unix Manual Pages
|
