int i_ToWidth = i_width;

            int i_ToHeight = i_height;

            int x = 0;

            int y = 0;

            int i_OriginalWidth = img_OriginalImage.Width;

            int i_OriginalHeight = img_OriginalImage.Height;

            switch(str_mode)

            {

                case "HW": //按照指定的高度和宽度进行缩放（可能变形）

                    break;

                case "W" : //指定宽度，高度按照比例缩放

                    i_ToHeight = img_OriginalImage.Height*i_width/img_OriginalImage.Width;

                    break;

                case "H" : //指定高度，宽度按照比例缩放

                    i_ToWidth = img_OriginalImage.Width*i_Height/img_OriginalImage.Height;

                    break;

                case "CUT" : //按照指定的高度和宽度剪裁（不变形）

                    if ((double)img_OriginalImage.Width/(double)img_OriginalImage.Height > 

(double)i_ToWidth/(double)i_ToHeight)

                    {

                        i_OriginalHeight = img_OriginalImage.Height;

                        i_OriginalWidth = img_OriginalImage.Height*i_ToWidth/i_ToHeight;

                        y = 0;

                        x = (img_OriginalImage.Width-i_OriginalWidth)/2;

                    }

                    else

                    {

                        i_OriginalWidth = img_OriginalImage.Width;

                        i_OriginalHeight = img_OriginalImage.Width*i_Height/i_ToWidth;