截图

Question

怎么把一个放在image上的位图进行截图，即把某部分区域复制给另一个位图bitmap

Answer 1

可以参考下
http://www.cnblogs.com/del/archive/2010/04/25/1719631.html

Answer 2

procedure TForm12.btn1Click(Sender: TObject);
var
    Bitmap: TBitmap;
    DstRect, SrcRect: TRect;begin
  if self.image1.Picture.Bitmap.Empty then exit;
  Bitmap := TBitmap.Create;
  //给Bitmap赋值：
  Bitmap.Assign(image1.Picture.Graphic);  //要截取的区域：
SrcRect:=Rect(Round(Image1.Picture.Width/image1.Width*(shp1.Left-image1.Left)),
              Round(Image1.Picture.Height/image1.Height*(shp1.top-Image1.top)),
              Round(Image1.Picture.Width/image1.Width*shp1.Width)+Round(Image1.Picture.Width/image1.Width*(shp1.Left-image1.Left)),
              Round(Image1.Picture.Height/image1.Height*(shp1.Height))+Round(Image1.Picture.Height/image1.Height*(shp1.top-Image1.top)));
   DstRect := SrcRect;
   OffsetRect(DstRect, -DstRect.Left, -DstRect.Top);
  //确定img1的位图大小：
  img1.Picture.Bitmap.Width  :=Round(Image1.Picture.Width/image1.Width*shp1.Width);
  img1.Picture.Bitmap.Height :=Round(Image1.Picture.Height/image1.Height*shp1.Height);
  //截取图片到img1：
  img1.Canvas.CopyRect(DstRect, Bitmap.Canvas, SrcRect);
  Bitmap.Free;
end;这里是用一个矩形Shape1来选择截取区域的