How To Change Screen Resolution

Change the resolution of your screen.

Actually I've ever used this function for TV-based software development, because of TV-resolution.

 

{ 
The function NewRes can have the following result: 

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. 
} 

function NewRes(XRes,YRes:DWord):integer; 
var 
  DevMode:TDeviceMode; 
begin 
  EnumDisplaySettings(nil, 0, DevMode); 
  DevMode.dmFields:=DM_PELSWIDTH or DM_PELSHEIGHT; 
  DevMode.dmPelsWidth:=XRes; 
  DevMode.dmPelsHeight:=YRes; 
  Result:=ChangeDisplaySettings(DevMode, 0); 
end; 

procedure TForm1.Button1Click(Sender: TObject); 
begin 
  if NewRes(1024,768)=DISP_CHANGE_SUCCESSFUL then 
  begin 
    ShowMessage('Resolution changed.'); 
  end; 
end;