MD5

生成MD5

 		private string CreateMD5(string code)
        {
            MD5 md5 = new MD5CryptoServiceProvider();
            byte[] result = md5.ComputeHash(Encoding.UTF8.GetBytes(code));
            StringBuilder sb = new StringBuilder(32);
            for (int i = 0; i < result.Length; i++)
            {
                sb.Append(result[i].ToString("x").PadLeft(2, '0'));
            }
            return sb.ToString();
        }