网上一搜一大把，这是别人的，你先看看
procedure TForm1.FormCreate(Sender: TObject);
var
w1: TBitmap;
w2: TColor;
rgn: HRGN;
begin
w1:=TBitmap.Create;
w1.Assign(image1.Picture.Bitmap); //取得图片对象
w2:=w1.Canvas.Pixels[0, 0];
rgn:=CreateRegion(w1, w2, self.Handle); //生成窗体区域
if rgn <> 0 then
begin
SetWindowRgn(Handle, rgn, true); //设定窗体形状
end;
w1.Free;
end;
function Tform1.CreateRegion(wMask: TBitmap; wColor: TColor; hControl: THandle): HRGN;
var
dc, dc_c: HDC;
rgn: HRGN;
x, y: integer;
coord: TPoint;
line: boolean;
color: TColor;
begin
dc:=GetWindowDC(hControl); //取得窗口的DC
dc_c:=CreateCompatibleDC(dc);
SelectObject(dc_c, wMask.Handle);
BeginPath(dc); //开始绘制
for x:=0 to wMask.Width - 1 do //设定窗体的大小和形状
begin
line:=false;
for y:=0 to wMask.Height - 1 do
begin
color:=GetPixel(dc_c, x, y);
if not (color = wColor) then
begin
if not line then
begin
line:=true;
coord.x:=x;
coord.y:=y;
end;
end;
if (color = wColor) or (y = wMask.Height - 1) then
begin
if line then
begin
line:=false;
MoveToEx(dc, coord.x, coord.y, nil);
LineTo(dc, coord.x, y);
LineTo(dc, coord.x + 1, y);
LineTo(dc, coord.x + 1, coord.y);
CloseFigure(dc);
end;
end;
end;
end;
EndPath(dc); //结束绘制
rgn:=PathToRegion(dc);
ReleaseDC(hControl, dc); //释放DC
Result:=rgn;
end;
