改变文字背景颜色

procedure TForm1.Button1Click(Sender: TObject);
var
  OldTextColor : TColorRef;
  OldBkColor : TColorRef;
  OldBkMode : Integer;
begin
  OldTextColor := SetTextColor(Form1.Canvas.Handle, RGB(0, 0, 255));
  OldBkColor := SetBkColor(Form1.Canvas.Handle, RGB(255, 0, 0));
  OldBkMode := SetBkMode(Form1.Canvas.Handle, OPAQUE);
  TextOut(Form1.Canvas.Handle,
          100, 100,
          'Blue text on red Background',
          27);
  SetBkMode(Form1.Canvas.Handle, OldBkMode);
  SetBkColor(Form1.Canvas.Handle, OldBkColor);
  SetTextColor(Form1.Canvas.Handle, OldTextColor);
end;