DES加密與解密MD5加密幫助類

 public class TrialHelper
    {
        //預設密鑰向量
        private static byte[] Keys = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };

        /// <summary>
        /// DES加密字元串
        /// </summary>
        /// <param name="encryptString">待加密的字元串</param>
        /// <param name="encryptKey">加密密鑰,要求為8位</param>
        /// <returns>加密成功返回加密後的字元串，失敗返回源串</returns>
        public static string EncryptDES( string encryptString, string encryptKey = "" )
        {
            try
            {
                if (string.IsNullOrEmpty(encryptKey) || encryptKey.Length < 8)
                {
                    encryptKey = "winform01";
                }

                byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));
                byte[] rgbIV = Keys;
                byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
                DESCryptoServiceProvider dCSP = new DESCryptoServiceProvider();
                MemoryStream mStream = new MemoryStream();
                CryptoStream cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                return Convert.ToBase64String(mStream.ToArray());
            }
            catch
            {
                return encryptString;
            }
        }

        /// <summary>
        /// DES解密字元串
        /// </summary>
        /// <param name="decryptString">待解密的字元串</param>
        /// <param name="decryptKey">解密密鑰,要求為8位,和加密密鑰相同</param>
        /// <returns>解密成功返回解密後的字元串，失敗返源串</returns>
        public static string DecryptDES( string decryptString, string decryptKey = "" )
        {
            try
            {
                if (string.IsNullOrEmpty(decryptKey) || decryptKey.Length < 8)
                {
                    decryptKey = "winform01";
                }
                byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey.Substring(0, 8));
                byte[] rgbIV = Keys;
                byte[] inputByteArray = Convert.FromBase64String(decryptString);
                DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
                MemoryStream mStream = new MemoryStream();
                CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
                cStream.Write(inputByteArray, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                return Encoding.UTF8.GetString(mStream.ToArray());
            }
            catch
            {
                return decryptString;
            }
        }

        /// <summary>
        /// MD5數據加密
        /// </summary>
        /// <param name="sDataIn">加密欄位</param>
        /// <returns>加密後的字元串</returns>
        public static string GetMD5( string sDataIn )
        {
            System.Security.Cryptography.MD5CryptoServiceProvider md5 = new System.Security.Cryptography.MD5CryptoServiceProvider();
            byte[] bytValue, bytHash;
            bytValue = System.Text.Encoding.UTF8.GetBytes(sDataIn);
            bytHash = md5.ComputeHash(bytValue);
            md5.Clear();
            string sTemp = "";
            for (int i = 0; i < bytHash.Length; i++)
            {
                sTemp += bytHash[i].ToString("x").PadLeft(2, '0');
            }
            return sTemp;
        }
    }

調用：

                //獲取登錄信息
                loginRecord.Name = tbName.Text.Trim();
                loginRecord.MD5Pwd = TrialHelper.GetMD5(tbPwd.Password); //保存到資料庫MD5加密方式
                loginRecord.Pwd = TrialHelper.EncryptDES(tbPwd.Password);//記住密碼des加密方式，保存到本地