MD5加密方法32位小写

        /// <summary>
        /// MD5加密(32位小写)
        /// </summary>
        /// <param name="str">加密字符</param>
        /// <returns></returns>
        public static string to_MD5(string str)
        {
            MD5 md5 = new MD5CryptoServiceProvider();
            byte[] fromData = System.Text.Encoding.UTF8.GetBytes(str);
            byte[] targetData = md5.ComputeHash(fromData);
            string byte2String = null;
            for (int i = 0; i < targetData.Length; i++)
            {
                byte2String = byte2String + targetData[i].ToString("x2");
            }

            return byte2String;
        }

Base64加密方式：

        /// <summary>
        /// Base64
        /// </summary>
        /// <param name="source"></param>
        /// <returns></returns>
        public string EncryptBase64(string source)
        {
            byte[] bytes = Encoding.UTF8.GetBytes(source);
            return Convert.ToBase64String(bytes);
        }