#region MD5算法public string md5(string str, int code){if (code == 32) //32位加密{return System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(str, "MD5").ToLower();}else //16位MD5加密（取32位加密的9~25字符）{return System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(str, "MD5").ToLower().Substring(8, 16);}}#endregion

#region DESEncrypt DES加密// <summary>/// 進行DES加密。/// </summary>/// <param name=”pToEncrypt”>要加密的字符串。</param>/// <param name=”sKey”>密鑰，且必須為8位。</param>/// <returns>以Base64格式返回的加密字符串。</returns>public string DESEncrypt(string pToEncrypt, string sKey){using (DESCryptoServiceProvider des = new DESCryptoServiceProvider()){byte[] inputByteArray = Encoding.UTF8.GetBytes(pToEncrypt);des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);System.IO.MemoryStream ms = new System.IO.MemoryStream();using (CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write)){cs.Write(inputByteArray, 0, inputByteArray.Length);cs.FlushFinalBlock();cs.Close();}string str = Convert.ToBase64String(ms.ToArray());ms.Close();return str;}}#endregion

#region DESDecrypt DES解密/// <summary>/// 進行DES解密。/// </summary>/// <param name=”pToDecrypt”>要解密的以Base64</param>/// <param name=”sKey”>密鑰，且必須為8位。</param>/// <returns>已解密的字符串。</returns>public string DESDecrypt(string pToDecrypt, string sKey){byte[] inputByteArray = Convert.FromBase64String(pToDecrypt);using (DESCryptoServiceProvider des = new DESCryptoServiceProvider()){des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);System.IO.MemoryStream ms = new System.IO.MemoryStream();using (CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write)){cs.Write(inputByteArray, 0, inputByteArray.Length);cs.FlushFinalBlock();cs.Close();}string str = Encoding.UTF8.GetString(ms.ToArray());ms.Close();return str;}}#endregion