C# 16进制字符串与byte数组互转

        /// <summary>
        /// byte[]转16进制格式string
        /// </summary>
        /// <param name="bytes"></param>
        /// <returns></returns>
        public static string ToHexString(byte[] bytes)
        {
            string returnStr = "";
            if (bytes != null)
            {
                for (int i = 0; i < bytes.Length; i++)
                { 
                    returnStr += bytes[i].ToString("X2") + " ";
                }
            }
            return returnStr;
        }        /// <summary>
        /// byte[]转16进