一段判断wap设备的代码

<?phpfunction ismobile() {    // 如果有HTTP_X_WAP_PROFILE则一定是移动设备    if (isset ($_SERVER['HTTP_X_WAP_PROFILE']))        return true;    //此条摘自TPM智能切换模板引擎，适合TPM开发    if(isset ($_SERVER['HTTP_CLIENT']) &&'PhoneClient'==$_SERVER['HTTP_CLIENT'])        return true;    //如果via信息含有wap则一定是移动设备,部分服务商会屏蔽该信息    if (isset ($_SERVER['HTTP_VIA']))        //找不到为flase,否则为true        return stristr($_SERVER['HTTP_VIA'], 'wap') ? true : false;    //判断手机发送的客户端标志,兼容性有待提高    if (isset ($_SERVER['HTTP_USER_AGENT'])) {        $clientkeywords = array(            'nokia','sony','ericsson','mot','samsung','htc','sgh','lg','sharp','sie-','philips','panasonic','alcatel','lenovo','iphone','ipod','blackberry','meizu','android','netfront','symbian','ucweb','windowsce','palm','operamini','operamobi','openwave','nexusone','cldc','midp','wap','mobile'        );        //从HTTP_USER_AGENT中查找手机浏览器的关键字        if (preg_match("/(" . implode('|', $clientkeywords) . ")/i", strtolower($_SERVER['HTTP_USER_AGENT']))) {            return true;        }    }    //协议法，因为有可能不准确，放到最后判断    if (isset ($_SERVER['HTTP_ACCEPT'])) {        // 如果只支持wml并且不支持html那一定是移动设备        // 如果支持wml和html但是wml在html之前则是移动设备        if ((strpos($_SERVER['HTTP_ACCEPT'], 'vnd.wap.wml') !== false) && (strpos($_SERVER['HTTP_ACCEPT'], 'textml') === false || (strpos($_SERVER['HTTP_ACCEPT'], 'vnd.wap.wml') < strpos($_SERVER['HTTP_ACCEPT'], 'textml')))) {            return true;        }    }    return false; } ?>