马虎，对于GDI +并不罕见。可以解决此问题：
Bitmap orig = new Bitmap(@"c:temp24bpp.bmp");Bitmap clone = new Bitmap(orig.Width, orig.Height, System.Drawing.Imaging.PixelFormat.Format32bppPArgb);using (Graphics gr = Graphics.FromImage(clone)) { gr.DrawImage(orig, new Rectangle(0, 0, clone.Width, clone.Height));}// Dispose orig as necessary...
