将ImageList中的图片转化成byte数组

  Image imgwd = this.imageList1.Images["wd.png"];
  var bytes = ImageToBytes(imgwd); 

 public byte[] ImageToBytes(Image image)
        {
            using (MemoryStream ms = new MemoryStream())
            {
                image.Save(ms, ImageFormat.Png);
                byte[] buffer = new byte[ms.Length];
                ms.Seek(0, SeekOrigin.Begin);
                ms.Read(buffer, 0, buffer.Length);
                return buffer;
            }
        }

　　获得的bytes就是需要的byte数组。