界面美化代码

1. 使控件产生圆角的方法（包括Tform）

procedure TfrmMessageDlg.SetBorder(AControl: TWinControl);
const
  ConRound = 5;

var
  LHrgn: HRGN;
begin
  LHrgn := 0;
  GetWindowRgn(AControl.Handle, LHrgn);
  DeleteObject(LHrgn);
  LHrgn := CreateRoundRectRgn(0, 0, AControl.Width, AControl.Height, ConRound, ConRound);
  SetWindowRgn(AControl.Handle, LHrgn, True);
end;

procedure TfrmMessageDlg.FormCreate(Sender: TObject);
begin
  pnlClient.Width := self.Width-2;
  pnlClient.Height := Self.Height -2;
  SetBorder(Self);
  SetBorder(pnlClient);
end;

设置form的Color为边框颜色，设置pnlClient设置Color为界面颜色

2. 设置非标准窗体标题的panel响应移动事件

procedure TfrmMessageDlg.FormCreate(Sender: TObject);
begin
  SetWindowLong(Self.Handle,GWL_STYLE,GetWindowLong(Self.Handle,GWL_STYLE) and not WS_CAPTION);
  Height := ClientHeight;
end;

procedure TfrmMessageDlg.pnl4MouseDown(Sender: TObject;
  Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
begin
  ReleaseCapture;
  (Self as TWinControl).Perform(WM_SYSCOMMAND,ConDragMove,0);
end;

3. 减少窗体上控件移动闪烁的问题可以用DoubleBuffered=true来解决即，是防闪烁，二还可以提高点效率。
一、CREATE BITMAP OR DC BUFFER
二、DRAW ON BITMAP
三、BITBLT BITMAP ON YOUR WINDOW。

4. 背景透明的图片问题

delphi7下只能用24bit的图片（即没有alpha通道的图片），要背景透明就只能TImage.Transparent := True;

delphi2010就可以支持32bit的图片了，启用alpha通道Image3.Transparent := False;

 Image3.Picture.Bitmap.AlphaFormat := afPremultiplied;

5. 渐进色的画法

procedure TfrmMain.DoDrawGradient(ACanvas: TCanvas; ATop, ALeft, AWidth,
  AHeight: Integer; AFColor, ATColor: TColor;ADirection: Byte);
//ADirection: 0:从左到右 1:从上到下
var
  LBmp: TBitmap;
  P: PByteArray;
  I, J, LFR, LFG, LFB, LTR, LTB, LTG,LR,LB,LG: Integer;
begin
  LBmp := TBitmap.Create;
  try
    LBmp.PixelFormat := pf24bit;
    LBmp.Width := AWidth;
    LBmp.Height := AHeight;
    LFR := GetRValue(ColorToRGB(AFColor));
    LFB := GetBValue(ColorToRGB(AFColor));
    LFG := GetGValue(ColorToRGB(AFColor));
    LTR := GetRValue(ColorToRGB(ATColor));
    LTB := GetBValue(ColorToRGB(ATColor));
    LTG := GetGValue(ColorToRGB(ATColor));
    for I := 0 to LBmp.Height - 1 do
    begin
      P := LBmp.ScanLine[I];
      case ADirection of
        0:for J := 0 to LBmp.Width - 1 do
        begin
          p[J * 3] := LTB + (AWidth - J) * (LFB - LTB) div AWidth;
          p[J * 3 + 1] := LTG + (AWidth - J) * (LFG - LTG) div AWidth;
          p[J * 3 + 2] := LTR + (AWidth - J) * (LFR - LTR) div AWidth;
        end;
        1:
        begin
          LR := LTR + (AHeight - I) * (LFR - LTR) div AHeight;
          LB := LTB + (AHeight - I) * (LFB - LTB) div AHeight;
          LG := LTG + (AHeight - I) * (LFG - LTG) div AHeight;
          for J := 0 to LBmp.Width - 1 do
          begin
            p[J * 3] := LB;
            p[J * 3 + 1] := LG;
            p[J * 3 + 2] := LR;
          end;
        end;
      end;
    end;
    //将缓冲区复制到目标上
    //pnlContent.Canvas.Draw(0,0,Lbmp);
    BitBlt(ACanvas.Handle,ALeft, ATop,  AWidth, AHeight, LBmp.Canvas.Handle, 0,0, SRCCOPY);
  finally
    FreeAndNil(LBmp);
  end;
end;

6. 输出字符的时候设置背景透明：

  SetBkMode(ACanvas.Handle,TRANSPARENT);
  ACanvas.TextOut(ARect.Left,ARect.Top,AText)