C# 的密碼編譯演算法

內建MD5、DSA、RSA加密，需要引入 using System.Security.Cryptography;

       // 32位MD5函數        public static string Md532(string str)        {            string cl = str;            string pwd = "";            MD5 md5 = MD5.Create();            byte[] s = md5.ComputeHash(Encoding.UTF8.GetBytes(cl));            for (int i = 0; i < s.Length; i++)            {                pwd = pwd + s[i].ToString("x");            }            return pwd;        }        // 16位MD5函數        public static string Md516(string ConvertString)        {            MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();            string t2 = BitConverter.ToString(md5.ComputeHash(UTF8Encoding.Default.GetBytes(ConvertString)), 4, 8);            t2 = t2.Replace("-", "");            t2 = t2.ToLower();            return t2;        }        public static string DSAEncrypt(string str)        {            byte[] bytes = Encoding.ASCII.GetBytes(str);            //選擇簽名方式，有RSA和DSA            DSACryptoServiceProvider dsac = new DSACryptoServiceProvider();            byte[] sign = dsac.SignData(bytes);            string strResult = Convert.ToString(sign);            return strResult;        }

DES加密

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Security.Cryptography;using System.IO;namespace DESHelper{    class DESJob    {        public static string encryptKey = "Oyea";    //定義密鑰         #region 加密字串        /// <summary> /// 加密字串          /// </summary>         /// <param name="str">要加密的字串</param>         /// <returns>加密後的字串</returns>         public static string Encrypt(string str)        {            DESCryptoServiceProvider descsp = new DESCryptoServiceProvider();   //執行個體化加/解密類對象              byte[] key = Encoding.Unicode.GetBytes(encryptKey); //定義位元組數組，用來儲存體金鑰               byte[] data = Encoding.Unicode.GetBytes(str);//定義位元組數組，用來儲存要加密的字串             MemoryStream MStream = new MemoryStream(); //執行個體化記憶體流對象                 //使用記憶體流執行個體化加密流對象              CryptoStream CStream = new CryptoStream(MStream, descsp.CreateEncryptor(key, key), CryptoStreamMode.Write);            CStream.Write(data, 0, data.Length);  //向加密流中寫入資料                 CStream.FlushFinalBlock();              //釋放加密流                 return Convert.ToBase64String(MStream.ToArray());//返回加密後的字串         }        #endregion        #region 解密字串        /// <summary>         /// 解密字串          /// </summary>         /// <param name="str">要解密的字串</param>         /// <returns>解密後的字串</returns>         public static string Decrypt(string str)        {            DESCryptoServiceProvider descsp = new DESCryptoServiceProvider();   //執行個體化加/解密類對象               byte[] key = Encoding.Unicode.GetBytes(encryptKey); //定義位元組數組，用來儲存體金鑰               byte[] data = Convert.FromBase64String(str);//定義位元組數組，用來儲存要解密的字串             MemoryStream MStream = new MemoryStream(); //執行個體化記憶體流對象                 //使用記憶體流執行個體化解密流對象                  CryptoStream CStream = new CryptoStream(MStream, descsp.CreateDecryptor(key, key), CryptoStreamMode.Write);            CStream.Write(data, 0, data.Length);      //向解密流中寫入資料                CStream.FlushFinalBlock();               //釋放解密流                 return Encoding.Unicode.GetString(MStream.ToArray());       //返回解密後的字串         }        #endregion    }}