C#加密解密方法,C#一個加密解密的方法,字串密碼編譯演算法

1、方法一 (無法復原加密)

 

 

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)

 

    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)

 

       
        const string KEY_64 = "VavicApp";//注意了，是8個字元，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無法復原加密

    (32位加密)

public string GetMD5(string s, string _input_charset)
    {

        /**//**//**//// <summary>
        /// 與ASP相容的MD5密碼編譯演算法
        /// </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)

 

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、加解文字檔

 

    //加密檔案
    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();
    }

    //解密檔案
    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();
    }
 

6、

using System;
using System.Collections.Generic;
using System.Text;
using System.Security.Cryptography;
using System.IO;

namespace Component
{
    public class Security
    {
        public Security()
        {
       
        }

        //預設密鑰向量
        private static byte[] Keys = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
        /**//**//**//**//**//**//**//// <summary>
        /// DES加密字串
        /// </summary>
        /// <param name="encryptString">待加密的字串</param>
        /// <param name="encryptKey">加密金鑰,要求為8位</param>
        /// <returns>加密成功返回加密後的字串，失敗返回源串</returns>
        public static string EncryptDES(string encryptString, string encryptKey)
        {
            try
            {
                byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));
                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, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                return Convert.ToBase64String(mStream.ToArray());
            }
            catch
            {
                return encryptString;
            }
        }

        /**//**//**//**//**//**//**//// <summary>
        /// DES解密字串
        /// </summary>
        /// <param name="decryptString">待解密的字串</param>
        /// <param name="decryptKey">解密密鑰,要求為8位,和加密金鑰相同</param>
        /// <returns>解密成功返回解密後的字串，失敗返源串</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, 0, inputByteArray.Length);
                cStream.FlushFinalBlock();
                return Encoding.UTF8.GetString(mStream.ToArray());
            }
            catch
            {
                return decryptString;
            }
        }

    }
}

 

 

 

 

 

C#一個加密解密的方法

using System;

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

namespace EncryptionDecryption
{
    ///
    /// 加密解密
    ///
    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;
        }
    }

    public class test
    {
        public static void aa()
        {
            EncryptionDecryption inter = new EncryptionDecryption();
            Console.WriteLine(((IBindesh)inter).encode("aa"));
            System.Console.ReadLine();
        }
    }
}

/*************************字串密碼編譯演算法***********************/
public string EncryptString(string str)
  {
   char[] Base64Code=new char[]{'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z','0','1','2','3','4','5','6','7','8','9','+','/','='};
   byte empty=(byte)0;
   System.Collections.ArrayList byteMessage=new  System.Collections.ArrayList(System.Text.Encoding.Default.GetBytes(str));
   System.Text.StringBuilder outmessage;
   int messageLen=byteMessage.Count;
   int page=messageLen/3;
   int use=0;
   if((use=messageLen%3)>0)
   {
    for(int i=0;i<3-use;i++)
     byteMessage.Add(empty);
    page++;
   }
   outmessage=new System.Text.StringBuilder(page*4);
   for(int i=0;i<page;i++)
   {
    byte[] instr = new byte[3];
    instr[0]=(byte)byteMessage[i*3];
    instr[1]=(byte)byteMessage[i*3+1];
    instr[2]=(byte)byteMessage[i*3+2];
    int[] outstr=new int[4];
    outstr[0]=instr[0]>>2;
 
    outstr[1]=((instr[0]&0x03)<<4)^(instr[1]>>4);
    if(!instr[1].Equals(empty))
     outstr[2]=((instr[1]&0x0f)<<2)^(instr[2]>>6);
    else
     outstr[2]=64;
    if(!instr[2].Equals(empty))
     outstr[3]=(instr[2]&0x3f);
    else
     outstr[3]=64;
    outmessage.Append(Base64Code[outstr[0]]);
    outmessage.Append(Base64Code[outstr[1]]);
    outmessage.Append(Base64Code[outstr[2]]);
    outmessage.Append(Base64Code[outstr[3]]);
   }
   return outmessage.ToString();
  }
/**************************************************字串解密演算法**************************************************/
public string DecryptString(string str)
              {
   if((str.Length%4)!=0)
   {
    throw new ArgumentException("不是正確的BASE64編碼，請檢查。","str");
   }
   if(!System.Text.RegularExpressions.Regex.IsMatch(str,"^[A-Z0-9/+=]*$",System.Text.RegularExpressions.RegexOptions.IgnoreCase))
   {
    throw new ArgumentException("包含不正確的BASE64編碼，請檢查。","str");
   }
   string Base64Code="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789+/=";
   int page=str.Length/4;
   System.Collections.ArrayList outMessage=new System.Collections.ArrayList(page*3);
   char[] message=str.ToCharArray();
   for(int i=0;i<page;i++)
   {
    byte[] instr=new byte[4];
    instr[0]=(byte)Base64Code.IndexOf(message[i*4]);
    instr[1]=(byte)Base64Code.IndexOf(message[i*4+1]);
    instr[2]=(byte)Base64Code.IndexOf(message[i*4+2]);
    instr[3]=(byte)Base64Code.IndexOf(message[i*4+3]);
    byte[] outstr=new byte[3];
    outstr[0]=(byte)((instr[0]<<2)^((instr[1]&0x30)>>4));
    if(instr[2]!=64)
    {
     outstr[1]=(byte)((instr[1]<<4)^((instr[2]&0x3c)>>2));
    }
    else
    {
     outstr[2]=0;
    }
    if(instr[3]!=64)
    {
     outstr[2]=(byte)((instr[2]<<6)^instr[3]);
    }
    else
    {
     outstr[2]=0;
    }
    outMessage.Add(outstr[0]);
    if(outstr[1]!=0)
     outMessage.Add(outstr[1]);
    if(outstr[2]!=0)
     outMessage.Add(outstr[2]);
   }
   byte[] outbyte=(byte[])outMessage.ToArray(Type.GetType("System.Byte"));
   return System.Text.Encoding.Default.GetString(outbyte);
  
  }
檔案的加密解密說明：
  
    在對檔案進行加密解密時，先將檔案的內容讀取到一個字串變數中，然後對字串加密，最後再把加密後的字串寫入到檔案中。詳見:
檔案操作.txt。