uses Windows;

 

procedure ClearConsoleWindow;

var

 ConsoleHandle:THandle;

 ConsoleInfo: TConsoleScreenBufferInfo;

 Coord:TCoord;

 WrittenChars:DWORD;

begin

 FillChar(ConsoleInfo,SizeOf(TConsoleScreenBufferInfo),0);

 FillChar(Coord,SizeOf(TCoord),0);

 ConsoleHandle:=GetStdHandle(STD_OUTPUT_HANDLE);

 GetConsoleScreenBufferInfo(ConsoleHandle, ConsoleInfo);

 FillConsoleOutputCharacter(ConsoleHandle,' ', ConsoleInfo.dwSize.X * ConsoleInfo.dwSize.Y, Coord, WrittenChars);

 SetConsoleCursorPosition(ConsoleHandle,ConsoleInfo.dwCursorPosition)

end;