/** * 简单对称加密算法之加密 * @param String $string 需要加密的字串 * @param String $skey 加密EKY * @return String */function encode($string = '', $skey = 'testphp') {　　$skey = str_split(base64_encode($skey));　　$strArr = str_split(base64_encode($string));　　$strCount = count($strArr);　　foreach ($skey as $key => $value) {　　　　$key < $strCount && $strArr[$key].=$value;　　}　　return str_replace('=', 'O0O0O', join('', $strArr));}

/** * 简单对称加密算法之解密 * @param String $string 需要解密的字串 * @param String $skey 解密KEY * @return String */function decode($string = '', $skey = 'testphp') {　　$skey = str_split(base64_encode($skey));　　$strArr = str_split(str_replace('O0O0O', '=', $string), 2);　　$strCount = count($strArr);　　foreach ($skey as $key => $value) {　　　　$key < $strCount && $strArr[$key][1] === $value && $strArr[$key] = $strArr[$key][0];　　}　　return base64_decode(join('', $strArr));}

//字符串转换成16进制function str2hex($str, $encoded = 'GBK') {　　$hex = '';　　if ($encoded == 'GBK') {　　　　$str = mb_convert_encoding($str, 'GBK', 'UTF-8');　　}　　for ($i = 0, $length = mb_strlen($str); $i < $length; $i++) {　　　　$hex .= dechex(ord($str{$i}));　　}　　return $hex;}

//16进制转换成字符串function hex2str($hex, $encoded = 'GBK') {　　$str = '';　　$arr = str_split($hex, 2);　　foreach ($arr as $bit) {　　　　$str .= chr(hexdec($bit));　　}　　if ($encoded == 'GBK') {　　　　$str = mb_convert_encoding($str, 'UTF-8', 'GBK');　　}　　return $str;}