A simple encryption and decryption code for PHP

  Share a PHP encryption and decryption class, when the user is registered to send mail validation when the estimated use of the code as follows

    Code as follows: Class syscrypt{ private $crypt _key= ' http://www.jb51.net ';//key  public function __ Construct ($crypt _key) {  $this->crypt_key= $crypt _key;  }  public function Encrypt ($txt) {  Srand (Double) microtime () *1000000);   $encrypt _key=md5 (rand (0,32000));   $CTR = 0;   $tmp = ';   for ($i =0 $i <strlen ($txt); $i + +) {    $ctr = $ctr ==strlen ($encrypt _key) 0: $ctr;     $tmp. =$ encrypt_key[$ctr]. ($txt [$i]^ $encrypt _key[$ctr + +]);  }   return Base64_encode (Self::__key ($tmp, $this->crypt_key)); &NBSP}  public function Decrypt ($txt) {  $txt =self::__key (Base64_decode ($txt), $this->crypt_key);   $tmp = ';   for ($i =0 $i <strlen ($txt); $i + +) {    $MD 5= $txt [$i];     $tmp. = $txt [+ + $i]^ $MD 5;  }   return $tmp; &NBSP}  private function __key ($txt, $encrypt _key) {  $encrypt _key=md5 ($encrypt _key);   $CTR =0;   $ Tmp= ';   for ($i =0; $i <strlen ($txt);$i + +) {    $ctr = $ctr ==strlen ($encrypt _key) 0: $ctr     $tmp. = $txt [$i]^ $encrypt _key[$ctr + +];  }   return $tmp; &NBSP}  public function __destruct () {  $this->crypt_key=null;  }}     How this class is used:   code is as follows: $SC =new syscrypt (' http://www.jb51.net '); $text = ' yhm.1234@163.com '; $test 1= $sc->encrypt ($text); Echo ' original: ', $text; echo ' <br/> '; Echo ' ciphertext: ', $test 1; echo "<br/>"; Echo ' Decrypt: ', $sc->decrypt ($test 1);     Output similar:   Original: yhm.1234@163.com cipher: bs8dbfu6aiocnfflvgzqmgrgbduoylezbxoazgo0bjk= decryption: yhm.1234@163.com