C#加密算法汇总

 方法一：
     //须添加对System.Web的引用
     using System.Web.Security; 

     ... 

     /// <summary>
     /// SHA1加密字符串
     /// </summary>
     /// <param name="source">源字符串</param>
     /// <returns>加密后的字符串</returns>
     public string SHA1(string source)
     {
         return FormsAuthentication.HashPasswordForStoringInConfigFile(source, "SHA1");
     } 

     /// <summary>
     /// MD5加密字符串
     /// </summary>
     /// <param name="source">源字符串</param>
     /// <returns>加密后的字符串</returns>
     public string MD5(string source)
     {
         return FormsAuthentication.HashPasswordForStoringInConfigFile(source, "MD5");;
     }

 方法二(可逆加密解密)：
     using System.Security.Cryptography; 

     ... 

     public string Encode(string data)
     {
         byte[] byKey = System.Text.ASCIIEncoding.ASCII.GetBytes(KEY_64);
         byte[] byIV = System.Text.ASCIIEncoding.ASCII.GetBytes(IV_64); 

         DESCryptoServiceProvider cryptoProvider = new DESCryptoServiceProvider();
         int i = cryptoProvider.KeySize;
         MemoryStream ms = new MemoryStream();
         CryptoStream cst = new CryptoStream(ms, cryptoProvider.CreateEncryptor(byKey, byIV), CryptoStreamMode.Write); 

         StreamWriter sw = new StreamWriter(cst);
         sw.Write(data);
         sw.Flush();
         cst.FlushFinalBlock();
         sw.Flush();
         return Convert.ToBase64String(ms.GetBuffer(), , (int)ms.Length); 

     } 

     public string Decode(string data)
     {
         byte[] byKey = System.Text.ASCIIEncoding.ASCII.GetBytes(KEY_64);
         byte[] byIV = System.Text.ASCIIEncoding.ASCII.GetBytes(IV_64); 

         byte[] byEnc;
         try
         {
             byEnc = Convert.FromBase64String(data);
         }
         catch
         {
             return null;
         } 

         DESCryptoServiceProvider cryptoProvider = new DESCryptoServiceProvider();
         MemoryStream ms = new MemoryStream(byEnc);
         CryptoStream cst = new CryptoStream(ms, cryptoProvider.CreateDecryptor(byKey, byIV), CryptoStreamMode.Read);
         StreamReader sr = new StreamReader(cst);
         return sr.ReadToEnd();
     }

 方法三(MD5不可逆)：
     using System.Security.Cryptography; 

     ... 

     //MD5不可逆加密 

     //32位加密 

     public string GetMD5_32(string s, string _input_charset)
     {
         MD5 md5 = new MD5CryptoServiceProvider();
         byte[] t = md5.ComputeHash(Encoding.GetEncoding(_input_charset).GetBytes(s));
         StringBuilder sb = new StringBuilder();
         for (int i = ; i < t.Length; i++)
         {
             sb.Append(t[i].ToString("x").PadLeft(, ''));
         }
         return sb.ToString();
     } 

     //16位加密
     public static string GetMd5_16(string ConvertString)
     {
         MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
         string t2 = BitConverter.ToString(md5.ComputeHash(UTF8Encoding.Default.GetBytes(ConvertString)), , );
         t2 = t2.Replace("-", "");
         return t2;
     }

 方法四(对称加密)：
     using System.IO;
     using System.Security.Cryptography; 

     ... 

     private SymmetricAlgorithm mobjCryptoService;
     private string Key;
     /// <summary>
     /// 对称加密类的构造函数
     /// </summary>
     public SymmetricMethod()
     {
         mobjCryptoService = new RijndaelManaged();
         Key = "Guz(%&hj7x89H$yuBI0456FtmaT5&fvHUFCy76*h%(HilJ$lhj!y6&(*jkP87jH7";
     }
     /// <summary>
     /// 获得密钥
     /// </summary>
     /// <returns>密钥</returns>
     private byte[] GetLegalKey()
     {
         string sTemp = Key;
         mobjCryptoService.GenerateKey();
         byte[] bytTemp = mobjCryptoService.Key;
         int KeyLength = bytTemp.Length;
         if (sTemp.Length > KeyLength)
             sTemp = sTemp.Substring(, 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 = "E4ghj*Ghg7!rNIfb&95GUY86GfghUb#er57HBh(u%g6HJ($jhWk7&!hg4ui%$hjk";
         mobjCryptoService.GenerateIV();
         byte[] bytTemp = mobjCryptoService.IV;
         int IVLength = bytTemp.Length;
         if (sTemp.Length > IVLength)
             sTemp = sTemp.Substring(, IVLength);
         else if (sTemp.Length < IVLength)
             sTemp = sTemp.PadRight(IVLength, ' ');
         return ASCIIEncoding.ASCII.GetBytes(sTemp);
     }
     /// <summary>
     /// 加密方法
     /// </summary>
     /// <param name="Source">待加密的串</param>
     /// <returns>经过加密的串</returns>
     public string Encrypto(string Source)
     {
         byte[] bytIn = UTF8Encoding.UTF8.GetBytes(Source);
         MemoryStream ms = new MemoryStream();
         mobjCryptoService.Key = GetLegalKey();
         mobjCryptoService.IV = GetLegalIV();
         ICryptoTransform encrypto = mobjCryptoService.CreateEncryptor();
         CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Write);
         cs.Write(bytIn, , bytIn.Length);
         cs.FlushFinalBlock();
         ms.Close();
         byte[] bytOut = ms.ToArray();
         return Convert.ToBase64String(bytOut);
     }
     /// <summary>
     /// 解密方法
     /// </summary>
     /// <param name="Source">待解密的串</param>
     /// <returns>经过解密的串</returns>
     public string Decrypto(string Source)
     {
         byte[] bytIn = Convert.FromBase64String(Source);
         MemoryStream ms = new MemoryStream(bytIn, , bytIn.Length);
         mobjCryptoService.Key = GetLegalKey();
         mobjCryptoService.IV = GetLegalIV();
         ICryptoTransform encrypto = mobjCryptoService.CreateDecryptor();
         CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Read);
         StreamReader sr = new StreamReader(cs);
         return sr.ReadToEnd();
     }

 方法五：
     using System.IO;
     using System.Security.Cryptography;
     using System.Text; 

     ... 

     //默认密钥向量
     private static byte[] Keys = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
     /// <summary>
     /// DES加密字符串
     /// </summary>
     /// <param name="encryptString">待加密的字符串</param>
     /// <param name="encryptKey">加密密钥,要求为8位</param>
     /// <returns>加密成功返回加密后的字符串，失败返回源串</returns>
     public static string EncryptDES(string encryptString, string encryptKey)
     {
         try
         {
             byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(, ));
             byte[] rgbIV = Keys;
             byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
             DESCryptoServiceProvider dCSP = new DESCryptoServiceProvider();
             MemoryStream mStream = new MemoryStream();
             CryptoStream cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
             cStream.Write(inputByteArray, , inputByteArray.Length);
             cStream.FlushFinalBlock();
             return Convert.ToBase64String(mStream.ToArray());
         }
         catch
         {
             return encryptString;
         }
     } 

     /// <summary>
     /// DES解密字符串
     /// </summary>
     /// <param name="decryptString">待解密的字符串</param>
     /// <param name="decryptKey">解密密钥,要求为8位,和加密密钥相同</param>
     /// <returns>解密成功返回解密后的字符串，失败返源串</returns>
     public static string DecryptDES(string decryptString, string decryptKey)
     {
         try
         {
             byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey);
             byte[] rgbIV = Keys;
             byte[] inputByteArray = Convert.FromBase64String(decryptString);
             DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider();
             MemoryStream mStream = new MemoryStream();
             CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
             cStream.Write(inputByteArray, , inputByteArray.Length);
             cStream.FlushFinalBlock();
             return Encoding.UTF8.GetString(mStream.ToArray());
         }
         catch
         {
             return decryptString;
         }
     }

 方法六(文件加密)：
     using System.IO;
     using System.Security.Cryptography;
     using System.Text; 

     ... 

     //加密文件
     private static void EncryptData(String inName, String outName, byte[] desKey, byte[] desIV)
     {
         //Create the file streams to handle the input and output files.
         FileStream fin = new FileStream(inName, FileMode.Open, FileAccess.Read);
         FileStream fout = new FileStream(outName, FileMode.OpenOrCreate, FileAccess.Write);
         fout.SetLength(); 

         //Create variables to help with read and write.
         byte[] bin = new byte[]; //This is intermediate storage for the encryption.
         long rdlen = ;              //This is the total number of bytes written.
         long totlen = fin.Length;    //This is the total length of the input file.
         int len;                     //This is the number of bytes to be written at a time. 

         DES des = new DESCryptoServiceProvider();
         CryptoStream encStream = new CryptoStream(fout, des.CreateEncryptor(desKey, desIV), CryptoStreamMode.Write); 

         //Read from the input file, then encrypt and write to the output file.
         while (rdlen < totlen)
         {
             len = fin.Read(bin, , );
             encStream.Write(bin, , len);
             rdlen = rdlen + len;
         } 

         encStream.Close();
         fout.Close();
         fin.Close();
     } 

     //解密文件
     private static void DecryptData(String inName, String outName, byte[] desKey, byte[] desIV)
     {
         //Create the file streams to handle the input and output files.
         FileStream fin = new FileStream(inName, FileMode.Open, FileAccess.Read);
         FileStream fout = new FileStream(outName, FileMode.OpenOrCreate, FileAccess.Write);
         fout.SetLength(); 

         //Create variables to help with read and write.
         byte[] bin = new byte[]; //This is intermediate storage for the encryption.
         long rdlen = ;              //This is the total number of bytes written.
         long totlen = fin.Length;    //This is the total length of the input file.
         int len;                     //This is the number of bytes to be written at a time. 

         DES des = new DESCryptoServiceProvider();
         CryptoStream encStream = new CryptoStream(fout, des.CreateDecryptor(desKey, desIV), CryptoStreamMode.Write); 

         //Read from the input file, then encrypt and write to the output file.
         while (rdlen < totlen)
         {
             len = fin.Read(bin, , );
             encStream.Write(bin, , len);
             rdlen = rdlen + len;
         } 

         encStream.Close();
         fout.Close();
         fin.Close(); 

 }

 using System;
 using System.Security.Cryptography;//这个是处理文字编码的前提
 using System.Text;
 using System.IO;
 /// <summary>
 /// DES加密方法
 /// </summary>
 /// <param name="strPlain">明文</param>
 /// <param name="strDESKey">密钥</param>
 /// <param name="strDESIV">向量</param>
 /// <returns>密文</returns>
 public string DESEncrypt(string strPlain,string strDESKey,string strDESIV)
 {
  //把密钥转换成字节数组
  byte[] bytesDESKey=ASCIIEncoding.ASCII.GetBytes(strDESKey);
  //把向量转换成字节数组
  byte[] bytesDESIV=ASCIIEncoding.ASCII.GetBytes(strDESIV);
  //声明1个新的DES对象
  DESCryptoServiceProvider desEncrypt=new DESCryptoServiceProvider();
  //开辟一块内存流
  MemoryStream msEncrypt=new MemoryStream();
  //把内存流对象包装成加密流对象
  CryptoStream csEncrypt=new CryptoStream(msEncrypt,desEncrypt.CreateEncryptor(bytesDESKey,bytesDESIV),CryptoStreamMode.Write);
  //把加密流对象包装成写入流对象
  StreamWriter swEncrypt=new StreamWriter(csEncrypt);
  //写入流对象写入明文
  swEncrypt.WriteLine(strPlain);
  //写入流关闭
  swEncrypt.Close();
  //加密流关闭
  csEncrypt.Close();
  //把内存流转换成字节数组，内存流现在已经是密文了
  byte[] bytesCipher=msEncrypt.ToArray();
  //内存流关闭
  msEncrypt.Close();
  //把密文字节数组转换为字符串，并返回
  return UnicodeEncoding.Unicode.GetString(bytesCipher);
 }

 /// <summary>
 /// DES解密方法
 /// </summary>
 /// <param name="strCipher">密文</param>
 /// <param name="strDESKey">密钥</param>
 /// <param name="strDESIV">向量</param>
 /// <returns>明文</returns>
 public string DESDecrypt(string strCipher,string strDESKey,string strDESIV)
 {
  //把密钥转换成字节数组
  byte[] bytesDESKey=ASCIIEncoding.ASCII.GetBytes(strDESKey);
  //把向量转换成字节数组
  byte[] bytesDESIV=ASCIIEncoding.ASCII.GetBytes(strDESIV);
  //把密文转换成字节数组
  byte[] bytesCipher=UnicodeEncoding.Unicode.GetBytes(strCipher);
  //声明1个新的DES对象
  DESCryptoServiceProvider desDecrypt=new DESCryptoServiceProvider();
  //开辟一块内存流，并存放密文字节数组
  MemoryStream msDecrypt=new MemoryStream(bytesCipher);
  //把内存流对象包装成解密流对象
  CryptoStream csDecrypt=new CryptoStream(msDecrypt,desDecrypt.CreateDecryptor(bytesDESKey,bytesDESIV),CryptoStreamMode.Read);
  //把解密流对象包装成读出流对象
  StreamReader srDecrypt=new StreamReader(csDecrypt);
  //明文=读出流的读出内容
  string strPlainText=srDecrypt.ReadLine();
  //读出流关闭
  srDecrypt.Close();
  //解密流关闭
  csDecrypt.Close();
  //内存流关闭
  msDecrypt.Close();
  //返回明文
  return strPlainText;
 }

本文转自：http://www.cnblogs.com/zengxiangzhan/archive/2010/01/30/1659687.html