{$APPTYPE CONSOLE}
// commandline use:      DisplayMode 800 600 256 85
// no arguments: it will list all modi.
program DisplayMode;

uses
  SysUtils, Messages, Windows;

{$R *.RES}

var
  i: Integer;
  DevMode: TDevMode;

begin
  i := 0;
  if ParamCount=0 then
  begin
    while EnumDisplaySettings(nil, i, DevMode) do
    begin
      with DevMode do
        Writeln(Format('%dx%d %d Colors, %d Hz', [dmPelsWidth, dmPelsHeight,
                       Int64(1) shl dmBitsperPel, dmDisplayFrequency]));
      inc(i);
    end;
    Writeln('-----');
    Writeln('Usage:   DisplayMode    ');
    Writeln('Example: DisplayMode 800 600 65536 85');
  end
  else
  begin
    while EnumDisplaySettings(nil, i, DevMode) do
    begin
      with DevMode do
      begin
        if (paramstr(1)=IntToStr(dmPelsWidth)) and
           (paramstr(2)=IntToStr(dmPelsHeight)) and
           (paramstr(3)=IntToStr(Int64(1) shl dmBitsperPel)) and
           (paramstr(4)=IntToStr(dmDisplayFrequency)) then
        begin
          ChangeDisplaySettings(DevMode, CDS_UPDATEREGISTRY);
          SendMessage(HWND_BROADCAST, WM_DISPLAYCHANGE, SPI_SETNONCLIENTMETRICS, 0);
          break;
        end;
      end;
      inc(i);
    end
  end;
end.