用C#实现DES加密解密封装

using  System; using  System.Security.Cryptography; using  System.Text; using  System.IO; namespace  Common ... {    /**//// <summary>    /// DESEncrypt加密解密算法。    /// </summary>    public sealed class DESEncrypt    ...{        private DESEncrypt()        ...{            //            // TODO: 在此处添加构造函数逻辑            //        }        private static string key = "zhoufoxcn";        /**//// <summary>        /// 对称加密解密的密钥        /// </summary>        public static string Key        ...{            get            ...{                return key;            }            set            ...{                key = value;            }        }        /**//// <summary>        /// DES加密        /// </summary>        /// <param name="encryptString"></param>        /// <returns></returns>        public static string DesEncrypt(string encryptString)        ...{            byte[] keyBytes = Encoding.UTF8.GetBytes(key.Substring(0, 8));            byte[] keyIV = keyBytes;            byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);            DESCryptoServiceProvider provider = new DESCryptoServiceProvider();            MemoryStream mStream = new MemoryStream();            CryptoStream cStream = new CryptoStream(mStream, provider.CreateEncryptor(keyBytes, keyIV), CryptoStreamMode.Write);            cStream.Write(inputByteArray, 0, inputByteArray.Length);            cStream.FlushFinalBlock();            return Convert.ToBase64String(mStream.ToArray());        }        /**//// <summary>        /// DES解密        /// </summary>        /// <param name="decryptString"></param>        /// <returns></returns>        public static string DesDecrypt(string decryptString)        ...{            byte[] keyBytes = Encoding.UTF8.GetBytes(key.Substring(0, 8));            byte[] keyIV = keyBytes;            byte[] inputByteArray = Convert.FromBase64String(decryptString);            DESCryptoServiceProvider provider = new DESCryptoServiceProvider();            MemoryStream mStream = new MemoryStream();            CryptoStream cStream = new CryptoStream(mStream, provider.CreateDecryptor(keyBytes, keyIV), CryptoStreamMode.Write);            cStream.Write(inputByteArray, 0, inputByteArray.Length);            cStream.FlushFinalBlock();            return Encoding.UTF8.GetString(mStream.ToArray());        }    }}