function isMobile() {    // 如果有HTTP_X_WAP_PROFILE则一定是移动设备    if (isset ($_SERVER['HTTP_X_WAP_PROFILE'])) {    return true;    }    //如果via信息含有wap则一定是移动设备,部分服务商会屏蔽该信息    if (isset ($_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($_SERVER['HTTP_ACCEPT'], 'text/html') === false || (strpos($_SERVER['HTTP_ACCEPT'], 'vnd.wap.wml') < strpos($_SERVER['HTTP_ACCEPT'], 'text/html')))) {return true;    }    }    return false;
}echo isMobile();

function is_mobile(){
$user_agent = $_SERVER['HTTP_USER_AGENT'];
if(trim($user_agent) == '')return true;//如果客户端信息为空，我们也认为该设备为手机设备
$mobile_agents = Array("240x320","acer","acoon","acs-","abacho","ahong","airness","alcatel","amoi","android","anywhereyougo.com","applewebkit/525","applewebkit/532","asus","audio","au-mic","avantogo","becker","benq","bilbo","bird","blackberry","blazer","bleu","cdm-","compal","coolpad","danger","dbtel","dopod","elaine","eric","etouch","fly","fly_","fly-","go.web","goodaccess","gradiente","grundig","haier","hedy","hitachi","htc","huawei","hutchison","inno","ipad","ipaq","ipod","jbrowser","kddi","kgt","kwc","lenovo","lg","lg2","lg3","lg4","lg5","lg7","lg8","lg9","lg-","lge-","lge9","longcos","maemo","mercator","meridian","micromax","midp","mini","mitsu","mmm","mmp","mobi","mot-","moto","nec-","netfront","newgen","nexian","nf-browser","nintendo","nitro","nokia","nook","novarra","obigo","palm","panasonic","pantech","philips","phone","pg-","playstation","pocket","pt-","qc-","qtek","rover","sagem","sama","samu","sanyo","samsung","sch-","scooter","sec-","sendo","sgh-","sharp","siemens","sie-","softbank","sony","spice","sprint","spv","symbian","tablet","talkabout","tcl-","teleca","telit","tianyu","tim-","toshiba","tsm","up.browser","utec","utstar","verykool","virgin","vk-","voda","voxtel","vx","wap","wellco","wig browser","wii","windows ce","wireless","xda","xde","zte",'Opera Mini','Kindle','Silk/','Mobile','baidu Transcoder');
$is_mobile = false;
foreach($mobile_agents as $device){
if(stristr($user_agent,$device) !== FALSE){
$is_mobile = true;
break;
}
}
return $is_mobile;
}