key = $key;        }           /**           * @brief      设置加密计算方法          * @param string $cipher       计算方法          * @return     void          */        public function setCipher($cipher) {                $this->cipher = $cipher;        }           /**           * @brief      设置加密模式          * @param string $mode 加密模式          * @return     void          */        public function setMode($mode) {                $this->mode = $mode;        }           /**           * @brief      字符串加密          * @param string $data 加密字符串          * @return string      加密后的字符串          */        public function encrypt($data) {                $td = mcrypt_module_open($this->cipher, '', $this->mode, '');                $iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($td), $this->rand);                mcrypt_generic_init($td, $this->key, $iv);                $encrypt = mcrypt_generic($td, $data);                mcrypt_generic_deinit($td);                $encrypt = mcrypt_generic($td, $data);                mcrypt_generic_deinit($td);                mcrypt_module_close($td);                return $iv . $encrypt;        }        /**          * @brief      字符串解密          * @param string $data 解密的字符串          * @return string      解密后的字符串          */        public function decrypt($data) {                $td = mcrypt_module_open($this->cipher, '', $this->mode, '');                $size = mcrypt_enc_get_iv_size($td);                $iv = mb_substr($data, 0, $size, 'latin1');                mcrypt_generic_init($td, $this->key, $iv);                $data = mb_substr($data, $size, mb_strlen($data, 'latin1'), 'latin1');                $decrypt = mdecrypt_generic($td, $data);                mcrypt_generic_deinit($td);                mcrypt_module_close($td);                return trim($decrypt);        }}?>