颜色渐变（在线等待！）

Question

请问高手，如何使form从上到下颜色逐渐变淡，而不是同一种浓度的色彩？
非常紧急，请多多帮忙！

Answer 1

procedure TForm1.SEChange(Sender: TObject);
begin
  AlphaBlend := Byte(SE.Value);
end;添加一个ColorDialog控件
procedure TForm1.btnColorClick(Sender: TObject);
begin
  ColorDialog.Color := pnlCaptionParent.Color;
  if ColorDialog.Execute then
    pnlCaptionParent.Color := ColorDialog.Color;
end;

Answer 2

var BMP:TBITMAP;
   i,IntColor:integer;
begin
    BMP:=TBitMap.Create();
    BMP.Width :=self.Width;
    BMP.Height :=self.Height;
    BMP.Canvas.Pen.Style:=psSolid;
    BMP.canvas.Pen.Mode:=pmCopy;
    BMP.Canvas.Pen.Width :=1;    for i:=0 to self.Height do
    begin
       IntColor:=255*i div self.Height;
       BMP.Canvas.pen.Color:=RGB(IntColor,IntColor,IntColor);
       BMP.Canvas.MoveTo(0,i);
       BMP.Canvas.LineTo(self.Width,i);
       self.Memo1.Lines.Add('i:'+IntTOstr(i)+'Color'+IntToStr(IntColor));
     end;
     BitBlt(GetDC(self.Handle),0,0,self.Width
         ,self.Height,Bmp.Canvas.Handle,0,0,srcCopy);
    BMP.Free();