⤷ Create a gradient filled form

Put this code in Forms OnPaint event:

procedure TForm1.FormPaint(Sender: TObject);
var
  Row, Ht: Word;
begin
  Ht:=(ClientHeight+255) div 256;
  for Row:=0 to 255 do
    with Canvas do 
    begin
      Brush.Color:=RGB(Row,0,0);
      FillRect(Rect(0,Row*Ht,ClientWidth,(Row+1)*Ht));
    end;
end;
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