DESCryptoServiceProvider数据加密标准应用

╰半夏微凉° 2022-07-13 12:19 209阅读 0赞

using  System;  
using  System.Collections.Generic;  
using  System.Linq;  
using  System.Text;  
using  System.Security.Cryptography;  
using  System.IO;  
  
namespace  EncryptDemo  
\{   
     class  Program  
    \{   
         static   void  Main( string \[\] args)  
        \{   
             //  Create a new DES key.   
             DESCryptoServiceProvider key =  new  DESCryptoServiceProvider();  
  
             // get the input   
              string  val =  null ;  
            val=Console.ReadLine().ToString();  
  
             //  Encrypt a string to a byte array   
              byte \[\] encryptedByte = Encrypt(val, key);  
  
             // write out the encrypt result   
              if  (encryptedByte !=  null )  
                 for  ( int  i =  0 ; i < encryptedByte.Length; i++)  
                \{   
                    Console.Write(encryptedByte\[i\]);  
                \}  
  
             // Decrypt the encrypted byte array   
             val = Decrypt(encryptedByte, key);  
  
            Console.Write( " \\n " );  
  
             // write out the original data   
             Console.Write(val);  
  
            Console.ReadKey();  
        \}  
  
         ///   <summary>   
         ///  a method to encrypt the string to a byte array  
         ///   </summary>   
         ///   <param name="strToEncrypt"> the string need to encrypt </param>   
         ///   <param name="key">  the CSP DES key </param>   
         ///   <returns> a byte array </returns>   
          public   static   byte \[\] Encrypt( string  strToEncrypt,SymmetricAlgorithm key)  
        \{   
             // if the string is null, then return    
              if  (strToEncrypt ==  null )  
                 return   null ;  
  
             // create a memory stream   
             MemoryStream ms =  new  MemoryStream();  
  
             // create a cryptostream using memory stream and the CSP DES key.     
             CryptoStream encStream =  new  CryptoStream(ms, key.CreateEncryptor(), CryptoStreamMode.Write);  
  
             // Create a StreamWriter to write a string to the stream.   
             StreamWriter sw =  new  StreamWriter(encStream);  
  
             //  Write the strToEncrypt to the stream   
             sw.Write(strToEncrypt);  
  
             //  Close the StreamWriter and CryptoStream.   
             sw.Close();  
            encStream.Close();  
  
             //  Get an array of bytes that represents  
             //  the memory stream.   
              byte \[\] result = ms.ToArray();  
  
             //  Close the memory stream.   
             ms.Close();  
  
             //  Return the encrypted byte array.   
              return  result;  
        \}  
  
         ///   <summary>   
         ///  a method to decrypt a encrypted byte to its original string  
         ///   </summary>   
         ///   <param name="byteToDecrypt"> encrypted data, it must be a byte array </param>   
         ///   <param name="key"> the CSP DES key </param>   
         ///   <returns> original string </returns>   
          public   static   string  Decrypt( byte \[\] byteToDecrypt, SymmetricAlgorithm key)  
        \{   
             // create a memory stream, as it will in read mode, so it must be new with the byteToDecrypt   
             MemoryStream ms =  new  MemoryStream(byteToDecrypt);  
  
             // create a cryptostream using memory stream and the CSP DES key.     
             CryptoStream encStream =  new  CryptoStream(ms, key.CreateDecryptor(), CryptoStreamMode.Read);  
  
             //  Create a StreamReader for reading the stream.   
             StreamReader sr =  new  StreamReader(encStream);  
  
             string  result =  "" ;  
  
             //  Read the stream as a string.   
             result = sr.ReadLine();  
  
             //  Close the streams.   
             sr.Close();  
  
            encStream.Close();  
  
            ms.Close();  
  
             return  result;  
  
  
        \}  
    \}  
\}