C # DES encryption/Decryption string

 

 Using  System;  Using  System. text;  Using  System. Security. cryptography;  Using  System. IO;  //  Default key vector  Private   Static   Byte [] Keys = { 0x12 , 0x34 ,0x56 , 0x78 , 0x90 , 0xab , 0xcd , 0xef  };  ///   <Summary>  ///  DES encrypted string  ///   </Summary>  ///   <Param name = "encryptstring"> String to be encrypted  </Param>  ///   <Param name = "encryptkey">  Encryption key, which must be 8 bits  </Param>  ///   <Returns>  The encrypted string is returned successfully. If the encrypted string fails, the source string is returned.  </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 decryption string  ///   </Summary>  ///   <Param name = "decryptstring">  String to be decrypted  </Param>  ///   <Param name = "decryptkey">  Decryption key, which must be 8 bits, the same as the encryption key </Param>  ///   <Returns>  The decrypted string is returned successfully, and the source string fails to be returned.  </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 ;}}