图片与二进制的相互转换

 　　 /// <summary>
        /// 图片转成二进制
        /// </summary>
        /// <param name="UpFile"></param>
        /// <returns></returns>
        public static byte[] imageWrite(HttpPostedFile UpFile)
        {
            int FileLength = UpFile.ContentLength;      //记录文件长度
                if (FileLength == 0)
                {    //文件长度为零时
                    return null;
                }
                else
                {
                    Byte[] FileByteArray = new Byte[FileLength];    //图象文件临时储存Byte数组
                    Stream StreamObject = UpFile.InputStream;       //建立数据流对像
                    //读取图象文件数据，FileByteArray为数据储存体，0为数据指针位置、FileLnegth为数据长度
                    StreamObject.Read(FileByteArray, 0, FileLength);
                    return FileByteArray;
                }
        }

        /// <summary>
        /// 二进制转成图片
        /// </summary>
        /// <param name="imageBtye"></param>
        /// <returns></returns>
        public static System.Drawing.Image imageRead(byte[] imageBtye)
        {
            System.IO.MemoryStream ms = new System.IO.MemoryStream(imageBtye);
            System.Drawing.Image img = System.Drawing.Image.FromStream(ms);
            return img;
        }