Asp.Net 加密解密

#region DES加密解密
        /// <summary>
        /// DES加密
        /// </summary>
        /// <param name="strSource">待加密字串</param>
        /// <param name="key">32位Key值</param>
        /// <returns>加密后的字符串</returns>
        public string DESEncrypt(string strSource)
        {
            return DESEncrypt(strSource, DESKey);
        }
        public string DESEncrypt(string strSource, byte[] key)
        {
            SymmetricAlgorithm sa = Rijndael.Create();
            sa.Key = key;
            sa.Mode = CipherMode.ECB;
            sa.Padding = PaddingMode.Zeros;
            MemoryStream ms = new MemoryStream();
            CryptoStream cs = new CryptoStream(ms, sa.CreateEncryptor(), CryptoStreamMode.Write);
            byte[] byt = Encoding.Unicode.GetBytes(strSource);
            cs.Write(byt, 0, byt.Length);
            cs.FlushFinalBlock();
            cs.Close();
            return Convert.ToBase64String(ms.ToArray());
        }
        /// <summary>
        /// DES解密
        /// </summary>
        /// <param name="strSource">待解密的字串</param>
        /// <param name="key">32位Key值</param>
        /// <returns>解密后的字符串</returns>
        public string DESDecrypt(string strSource)
        {
            return DESDecrypt(strSource, DESKey);
        }
        public string DESDecrypt(string strSource, byte[] key)
        {
            SymmetricAlgorithm sa = Rijndael.Create();
            sa.Key = key;
            sa.Mode = CipherMode.ECB;
            sa.Padding = PaddingMode.Zeros;
            ICryptoTransform ct = sa.CreateDecryptor();
            byte[] byt = Convert.FromBase64String(strSource);
            MemoryStream ms = new MemoryStream(byt);
            CryptoStream cs = new CryptoStream(ms, ct, CryptoStreamMode.Read);
            StreamReader sr = new StreamReader(cs, Encoding.Unicode);
            return sr.ReadToEnd();
        }
        #endregion

        #region 一个用hash实现的加密解密方法
        /// <summary>
        /// 加密
        /// </summary>
        /// <param name="src"></param>
        /// <returns></returns>
        public static string EncryptStrByHash(string src)
        {
            if (src.Length == 0)
            {
                return "";
            }
            byte[] HaKey = System.Text.Encoding.ASCII.GetBytes((src + "Test").ToCharArray());
            byte[] HaData = new byte[20];
            HMACSHA1 Hmac = new HMACSHA1(HaKey);
            CryptoStream cs = new CryptoStream(Stream.Null, Hmac, CryptoStreamMode.Write);
            try
            {
                cs.Write(HaData, 0, HaData.Length);
            }
            finally
            {
                cs.Close();
            }
            string HaResult = System.Convert.ToBase64String(Hmac.Hash).Substring(0, 16);
            byte[] RiKey = System.Text.Encoding.ASCII.GetBytes(HaResult.ToCharArray());
            byte[] RiDataBuf = System.Text.Encoding.ASCII.GetBytes(src.ToCharArray());
            byte[] EncodedBytes =   { };
            MemoryStream ms = new MemoryStream();
            RijndaelManaged rv = new RijndaelManaged();
            cs = new CryptoStream(ms, rv.CreateEncryptor(RiKey, RiKey), CryptoStreamMode.Write);
            try
            {
                cs.Write(RiDataBuf, 0, RiDataBuf.Length);
                cs.FlushFinalBlock();
                EncodedBytes = ms.ToArray();
            }
            finally
            {
                ms.Close();
                cs.Close();
            }
            return HaResult + System.Convert.ToBase64String(EncodedBytes);
        }

        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="src"></param>
        /// <returns></returns>
        public static string DecrypStrByHash(string src)
        {
            if (src.Length < 40) return "";
            byte[] SrcBytes = System.Convert.FromBase64String(src.Substring(16));
            byte[] RiKey = System.Text.Encoding.ASCII.GetBytes(src.Substring(0, 16).ToCharArray());
            byte[] InitialText = new byte[SrcBytes.Length];
            RijndaelManaged rv = new RijndaelManaged();
            MemoryStream ms = new MemoryStream(SrcBytes);
            CryptoStream cs = new CryptoStream(ms, rv.CreateDecryptor(RiKey, RiKey), CryptoStreamMode.Read);
            try
            {
                cs.Read(InitialText, 0, InitialText.Length);
            }
            finally
            {
                ms.Close();
                cs.Close();
            }
            System.Text.StringBuilder Result = new System.Text.StringBuilder();
            for (int i = 0; i < InitialText.Length; ++i) if (InitialText[i] > 0) Result.Append((char)InitialText[i]);
            return Result.ToString();
        }

        /// <summary>
        /// 对加密后的密文重新编码,如果密文长>16,则去掉前16个字符,如果长度小于16,返回空字符串
        /// </summary>
        /// <param name="s"></param>
        /// <returns></returns>
        public string ReEncryptStrByHash(string s)
        {
            string e = Encrypt.EncryptStrByHash(s);
            return ((e.Length > 16) ? e.Substring(16) : "");
        }
        #endregion

        #region Md5加密,生成16位或32位,生成的密文都是大写
        public static string Md5To16(string str)
        {
            MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
            string t2 = BitConverter.ToString(md5.ComputeHash(UTF8Encoding.Default.GetBytes(str)), 4, 8);
            t2 = t2.Replace("-", "");
            return t2;
        }

        //// <summary>
        /// MD5　32位加密
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public static string Md5To32(string str)
        {
            string pwd = "";
            MD5 md5 = MD5.Create();
            byte[] s = md5.ComputeHash(Encoding.UTF8.GetBytes(str));
            for (int i = 0; i < s.Length; i++)
            {
                pwd = pwd + s[i].ToString("X");
            }
            return pwd;
        }
        #endregion

        #region 3DES加密解密
        public string Encrypt3DES(string str)
        {
            //密钥
            string sKey = "wyw308";
            //    //矢量,可为空
            string sIV = "scf521";
            //    //构造对称算法
            SymmetricAlgorithm mCSP = new TripleDESCryptoServiceProvider();

            ICryptoTransform ct;
            MemoryStream ms;
            CryptoStream cs;
            byte[] byt;
            mCSP.Key = Convert.FromBase64String(sKey);
            mCSP.IV = Convert.FromBase64String(sIV);
            mCSP.Mode = System.Security.Cryptography.CipherMode.ECB;
            mCSP.Padding = System.Security.Cryptography.PaddingMode.PKCS7;
            ct = mCSP.CreateEncryptor(mCSP.Key, mCSP.IV);
            byt = Encoding.UTF8.GetBytes(str);
            ms = new MemoryStream();
            cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
            cs.Write(byt, 0, byt.Length);
            cs.FlushFinalBlock();
            cs.Close();
            return Convert.ToBase64String(ms.ToArray());
        }
        /// <summary>
        /// 带指定密钥和矢量的3DES加密
        /// </summary>
        /// <param name="str"></param>
        /// <param name="sKey"></param>
        /// <param name="sIV"></param>
        /// <returns></returns>
        public string Encrypt3DES(string str, string sKey, string sIV)
        {
            SymmetricAlgorithm mCSP = new TripleDESCryptoServiceProvider();
            ICryptoTransform ct;
            MemoryStream ms;
            CryptoStream cs;
            byte[] byt;
            mCSP.Key = Convert.FromBase64String(sKey);
            mCSP.IV = Convert.FromBase64String(sIV);
            mCSP.Mode = System.Security.Cryptography.CipherMode.ECB;
            mCSP.Padding = System.Security.Cryptography.PaddingMode.PKCS7;
            ct = mCSP.CreateEncryptor(mCSP.Key, mCSP.IV);
            byt = Encoding.UTF8.GetBytes(str);
            ms = new MemoryStream();
            cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
            cs.Write(byt, 0, byt.Length);
            cs.FlushFinalBlock();
            cs.Close();
            return Convert.ToBase64String(ms.ToArray());
        }

        //解密
        public string Decrypt3DES(string Value)
        {
            string sKey = "wyw308";
            string sIV = "scf521";
            SymmetricAlgorithm mCSP = new TripleDESCryptoServiceProvider();
            ICryptoTransform ct;
            MemoryStream ms;
            CryptoStream cs;
            byte[] byt;
            mCSP.Key = Convert.FromBase64String(sKey);
            mCSP.IV = Convert.FromBase64String(sIV);
            mCSP.Mode = System.Security.Cryptography.CipherMode.ECB;
            mCSP.Padding = System.Security.Cryptography.PaddingMode.PKCS7;
            ct = mCSP.CreateDecryptor(mCSP.Key, mCSP.IV);
            byt = Convert.FromBase64String(Value);
            ms = new MemoryStream();
            cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
            cs.Write(byt, 0, byt.Length);
            cs.FlushFinalBlock();
            cs.Close();
            return Encoding.UTF8.GetString(ms.ToArray());
        }
        /// <summary>
        /// 带指定密钥和矢量的3DES解密
        /// </summary>
        /// <param name="Value"></param>
        /// <param name="sKey"></param>
        /// <param name="sIV"></param>
        /// <returns></returns>
        public string Decrypt3DES(string str, string sKey, string sIV)
        {
            SymmetricAlgorithm mCSP = new TripleDESCryptoServiceProvider();
            ICryptoTransform ct;
            MemoryStream ms;
            CryptoStream cs;
            byte[] byt;
            mCSP.Key = Convert.FromBase64String(sKey);
            mCSP.IV = Convert.FromBase64String(sIV);
            mCSP.Mode = System.Security.Cryptography.CipherMode.ECB;
            mCSP.Padding = System.Security.Cryptography.PaddingMode.PKCS7;
            ct = mCSP.CreateDecryptor(mCSP.Key, mCSP.IV);
            byt = Convert.FromBase64String(str);
            ms = new MemoryStream();
            cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
            cs.Write(byt, 0, byt.Length);
            cs.FlushFinalBlock();
            cs.Close();
            return Encoding.UTF8.GetString(ms.ToArray());
        }
        #endregion

        #region 一个简单的加密解密方法,只支持英文
        public static string EnCryptEnStr(string str) //倒序加1加密
        {
            byte[] by = new byte[str.Length];
            for (int i = 0;
             i <= str.Length - 1;
             i++)
            {
                by[i] = (byte)((byte)str[i] + 1);
            }
            str = "";
            for (int i = by.Length - 1;
             i >= 0;
             i--)
            {
                str += ((char)by[i]).ToString();
            }
            return str;
        }
        public static string DeCryptEnStr(string str) //顺序减1解码
        {
            byte[] by = new byte[str.Length];
            for (int i = 0;
             i <= str.Length - 1;
             i++)
            {
                by[i] = (byte)((byte)str[i] - 1);
            }
            str = "";
            for (int i = by.Length - 1;
             i >= 0;
             i--)
            {
                str += ((char)by[i]).ToString();
            }
            return str;
        }
        #endregion

        #region 一个简单的加密解密方法,在上一个的基础上支持中文
        public static string EnCryptCnStr(string str)
        {
            string htext = ""; // blank text

            for (int i = 0; i < str.Length; i++)
            {
                htext = htext + (char)(str[i] + 10 - 1 * 2);
            }
            return htext;
        }

        public static string DeCryptCnStr(string str)
        {
            string dtext = "";

            for (int i = 0; i < str.Length; i++)
            {
                dtext = dtext + (char)(str[i] - 10 + 1 * 2);
            }
            return dtext;
        }
        #endregion

        #region Url地址编码解码

        /// <summary>
        /// 编码Url地址
        /// </summary>
        /// <param name="url"></param>
        /// <returns></returns>
        public static string UrlEncode(string url)
        {
            byte[] mByte = null;
            mByte = System.Text.Encoding.GetEncoding("GB2312").GetBytes(url);

            return System.Web.HttpUtility.UrlEncode(mByte);
        }

        /// <summary>
        /// 解码Url地址
        /// </summary>
        /// <param name="url"></param>
        /// <returns></returns>
        public static string UrlDecode(string url)
        {
            return HttpUtility.UrlDecode(url, System.Text.Encoding.GetEncoding("GB2312"));
        }
        #endregion