using System; using System.IO; using System.Text; using System.Security.Cryptography; using System.Web; namespace Encryption.App_Code {     /// <summary>     /// 加密码类     /// </summary>     public class Encryption     {         /// <summary>         /// 加密         /// </summary>         /// <param name="inputString"></param>         /// <returns></returns>         public static string DesEncrypt(string inputString)         {             return DesEncrypt(inputString, Key);         }         /// <summary>         /// 解密         /// </summary>         /// <param name="inputString"></param>         /// <returns></returns>         public static string DesDecrypt(string inputString)         {             return DesDecrypt(inputString, Key);         }         /// <summary>         /// 密匙         /// </summary>         private static string Key         {             get             {                 return "hongye10";             }         }         /// <summary>         /// 加密字符串         /// 注意:密钥必须为８位         /// </summary>         /// <param name="strText">字符串</param>         /// <param name="encryptKey">密钥</param>         /// <param name="encryptKey">返回加密后的字符串</param>         public static string DesEncrypt(string inputString, string encryptKey)         {             byte[] byKey = null;             byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };             try             {                 byKey = System.Text.Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));                 DESCryptoServiceProvider des = new DESCryptoServiceProvider();                 byte[] inputByteArray = Encoding.UTF8.GetBytes(inputString);                 MemoryStream ms = new MemoryStream();                 CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(byKey, IV), CryptoStreamMode.Write);                 cs.Write(inputByteArray, 0, inputByteArray.Length);                 cs.FlushFinalBlock();                 return Convert.ToBase64String(ms.ToArray());             }             catch (System.Exception error)             {                 //return error.Message;                 return null;             }         }         /// <summary>         /// 解密字符串         /// </summary>         /// <param name="this.inputString">加了密的字符串</param>         /// <param name="decryptKey">密钥</param>         /// <param name="decryptKey">返回解密后的字符串</param>         public static string DesDecrypt(string inputString, string decryptKey)         {             byte[] byKey = null;             byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };             byte[] inputByteArray = new Byte[inputString.Length];             try             {                 byKey = System.Text.Encoding.UTF8.GetBytes(decryptKey.Substring(0, 8));                 DESCryptoServiceProvider des = new DESCryptoServiceProvider();                 inputByteArray = Convert.FromBase64String(inputString);                 MemoryStream ms = new MemoryStream();                 CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write);                 cs.Write(inputByteArray, 0, inputByteArray.Length);                 cs.FlushFinalBlock();                 System.Text.Encoding encoding = new System.Text.UTF8Encoding();                 return encoding.GetString(ms.ToArray());             }             catch (System.Exception error)             {                 //return error.Message;                 return null;             }         }     } }