c#加密 可逆与不可逆MD5 加密

1、方法一 (不可逆加密) srxljl

 

 

public string EncryptPassword( string PasswordString, string PasswordFormat )
    ... {
   string        encryptPassword = null;
   if (PasswordFormat="SHA1")...{
         encryptPassword=FormsAuthortication.HashPasswordForStoringInConfigFile(PasswordString ,"SHA1");
         }
         elseif (PasswordFormat="MD5")
   ...{ encryptPassword=FormsAuthortication.HashPasswordForStoringInConfigFile(PasswordString ,"MD5");
         }
return encryptPassword ;
}

 

2、方法二 (可逆加密)srxljl

 

     public interface IBindesh
... {
    string encode(string str);
    string decode(string str);
}

public class EncryptionDecryption : IBindesh
     ... {
        public string encode(string str)
        ...{
            string htext = "";

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

        public string decode(string str)
        ...{
            string dtext = "";

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

 

3、方法三 (可逆加密)srxljl

 

        
         const string KEY_64 = " VavicApp " ; // 注意了，是8个字符，64位

         const string IV_64 = " VavicApp " ;
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(), 0, (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();
              }

 

4,md5(32位加密) srxljl

public string GetMD5( string s, string _input_charset)
     ... {

        /**//// <summary>
        /// 与ASP兼容的MD5加密算法
        /// </summary>

             MD5 md5 = new MD5CryptoServiceProvider();
        byte[] t = md5.ComputeHash(Encoding.GetEncoding(_input_charset).GetBytes(s));
             StringBuilder sb = new StringBuilder(32);
        for (int i = 0; i < t.Length; i++)
        ...{
                 sb.Append(t[i].ToString("x").PadLeft(2, '0'));
             }
        return sb.ToString();
         }

        (16位加密)srxljl

 

public static string GetMd5Str( string ConvertString)
     ... {
             MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();
        string t2 = BitConverter.ToString(md5.ComputeHash(UTF8Encoding.Default.GetBytes(ConvertString)), 4, 8);
             t2 = t2.Replace("-", "");
        return t2;
         }

 

5、加解文本文件srxljl

 

     // 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(0);

        //Create variables to help with read and write.
        byte[] bin = new byte[100]; //This is intermediate storage for the encryption.
        long rdlen = 0;              //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, 0, 100);
                 encStream.Write(bin, 0, 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(0);

        //Create variables to help with read and write.
        byte[] bin = new byte[100]; //This is intermediate storage for the encryption.
        long rdlen = 0;              //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, 0, 100);
                 encStream.Write(bin, 0, len);
                 rdlen = rdlen + len;
             }

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