php-关于DES加密 求帮助！

 public class DESEncryptDecrypt    {        private string Key;        private string IV;        private DESCryptoServiceProvider IDes;        private byte[] GetKey;        private byte[] GetIV;        public DESEncryptDecrypt()        {            this.Key = "%&hj7x89H$yuBI0456FtmaT5&fvHUFCy76*h%(HilJ$lhj!y6&(*jkP87jH7&*^$^&*%&*%$@#@^";            this.IV = "E4ghj*Ghg7!rNIfb&95GUY86GfghUb#er57HBh(u%g6HJ($jhWk7&!hg4ui%$hjk";            this.Init();        }        public DESEncryptDecrypt(string Key)        {            this.Key = Key;            this.IV = "E4ghj*Ghg7!rNIfb&95GUY86GfghUb#er57HBh(u%g6HJ($jhWk7&!hg4ui%$hjk";            this.Init();        }        public DESEncryptDecrypt(string Key,string IV)        {            this.Key = Key;            this.IV = IV;            this.Init();        }        private void Init()        {            this.IDes = new DESCryptoServiceProvider();            this.IDes.GenerateKey();            this.GetKey = this.IDes.Key;            this.IDes.GenerateIV();            this.GetIV = this.IDes.IV;        }        /// <summary>        /// 获得密钥        /// </summary>        /// <returns>密钥</returns>        private byte[] GetLegalKey()        {            string sTemp = this.Key;            byte[] bytTemp = this.GetKey;            int KeyLength = bytTemp.Length;            if (sTemp.Length > KeyLength)            {                sTemp = sTemp.Substring(0, KeyLength);            }            else            {                if (sTemp.Length < KeyLength)                {                    sTemp = sTemp.PadRight(KeyLength, ' ');                }            }            return ASCIIEncoding.ASCII.GetBytes(sTemp);        }        /// <summary>        /// 获得初始向量IV        /// </summary>        /// <returns>初试向量IV</returns>        private byte[] GetLegalIV()        {            string sTemp = this.Key;            byte[] bytTemp = this.GetIV;            int IVLength = bytTemp.Length;            if (sTemp.Length > IVLength)            {                sTemp = sTemp.Substring(0, IVLength);            }            else            {                if (sTemp.Length < IVLength)                {                    sTemp = sTemp.PadRight(IVLength, ' ');                }            }            return ASCIIEncoding.ASCII.GetBytes(sTemp);        }        /// <summary>        /// 加密算法        /// </summary>        /// <param name="data"></param>        /// <returns></returns>        public string Encrypt(string data)        {            //将要加密的数据编码为字节数组            byte[] encrypt_data = System.Text.Encoding.UTF8.GetBytes(data);    //如果使用Unicode编码，支持中文加密            //创建流，保存加密后的数据            MemoryStream ms = new MemoryStream();            //创建加密流            CryptoStream cs = new CryptoStream(ms, this.IDes.CreateEncryptor(this.GetLegalKey(), this.GetLegalIV()), CryptoStreamMode.Write);            //调用Write方法将加密后的结果写到 流 中            cs.Write(encrypt_data, 0, encrypt_data.Length);            //将数据从流写入内存（这句不能少，否则在从内存导出到字符串的时候会出现字符丢失)            cs.FlushFinalBlock();            //ms.ToString(); ==>将流写入字节数组中            string result = Convert.ToBase64String(ms.ToArray());            ms.Close();            cs.Close();            return result;        }        /// <summary>        /// 解密算法        /// </summary>        /// <param name="data"></param>        /// <returns></returns>        public string Decrypt(string data)        {            byte[] decrypt_data = Convert.FromBase64String(data);            MemoryStream ms = new MemoryStream();            CryptoStream cs = new CryptoStream(ms, this.IDes.CreateDecryptor(this.GetLegalKey(), this.GetLegalIV()), CryptoStreamMode.Write);            cs.Write(decrypt_data, 0, decrypt_data.Length);            cs.FlushFinalBlock();            string result = System.Text.Encoding.UTF8.GetString(ms.ToArray());            ms.Close();            cs.Close();            return result;        }    }