Konsole leeren?

[nicodex]

Delphi-Quellcode:

program HelloWorld;

{$APPTYPE CONSOLE}

uses
  Windows,
  SysUtils;

function ClearConsoleScreen(): Boolean;
var
  ConsoleOutput: THandle;
  ConsoleScreenBufferInfo: TConsoleScreenBufferInfo;
  WriteCoord: TCoord;
  NumberOfCharsWritten: DWORD;
begin
  Result := False;
  ConsoleOutput := GetStdHandle(STD_OUTPUT_HANDLE);
  if ConsoleOutput <> INVALID_HANDLE_VALUE then
  begin
    if GetConsoleScreenBufferInfo(ConsoleOutput, ConsoleScreenBufferInfo) then
    begin
      WriteCoord.X := 0;
      WriteCoord.Y := 0;
      if FillConsoleOutputCharacter(ConsoleOutput, ' ',
        ConsoleScreenBufferInfo.dwSize.X * ConsoleScreenBufferInfo.dwSize.X,
        WriteCoord, NumberOfCharsWritten) then
      begin
        Result := SetConsoleCursorPosition(ConsoleOutput, WriteCoord);
      end;
    end;
  end;
end;

begin
  try
    WriteLn('Hallo');
    ClearConsoleScreen();
    WriteLn('World');
  except
    on E: Exception do
      Writeln(E.Classname, ': ', E.Message);
  end;
  ReadLn;
end.