php - 判断是用户通过手机还是电脑访问

<?
echo is_mobile_request()?"手机访问":"电脑访问";

function is_mobile_request()
{
	$_SERVER['ALL_HTTP'] = isset($_SERVER['ALL_HTTP'])?$_SERVER['ALL_HTTP'] : '';
	$mobile_browser = '0';
	if(preg_match('/(up.browser|up.link|mmp|symbian|smartphone|midp|wap|phone|iphone|ipad|ipod|android|xoom)/i',
	strtolower($_SERVER['HTTP_USER_AGENT'])))
		$mobile_browser++;
	if((isset($_SERVER['HTTP_ACCEPT'])) and 
	(strpos(strtolower($_SERVER['HTTP_ACCEPT']),'application/vnd.wap.xhtml+xml') !== false))
		$mobile_browser++;
	if(isset($_SERVER['HTTP_X_WAP_PROFILE']))
		$mobile_browser++;
	if(isset($_SERVER['HTTP_PROFILE']))
		$mobile_browser++;
	$mobile_ua = strtolower(substr($_SERVER['HTTP_USER_AGENT'],0,4));
	$mobile_agents = array(
	'w3c ','acs-','alav','alca','amoi','audi','avan','benq','bird','blac',
	'blaz','brew','cell','cldc','cmd-','dang','doco','eric','hipt','inno',
	'ipaq','java','jigs','kddi','keji','leno','lg-c','lg-d','lg-g','lge-',
	'maui','maxo','midp','mits','mmef','mobi','mot-','moto','mwbp','nec-',
	'newt','noki','oper','palm','pana','pant','phil','play','port','prox',
	'qwap','sage','sams','sany','sch-','sec-','send','seri','sgh-','shar',
	'sie-','siem','smal','smar','sony','sph-','symb','t-mo','teli','tim-',
	'tosh','tsm-','upg1','upsi','vk-v','voda','wap-','wapa','wapi','wapp',
	'wapr','webc','winw','winw','xda','xda-'
	);
	if(in_array($mobile_ua, $mobile_agents))
		$mobile_browser++;
	if(strpos(strtolower($_SERVER['ALL_HTTP']), 'operamini') !== false)
		$mobile_browser++;
	// Pre-final check to reset everything if the user is on Windows
	if(strpos(strtolower($_SERVER['HTTP_USER_AGENT']), 'windows') !== false)
		$mobile_browser=0;
	// But WP7 is also Windows, with a slightly different characteristic
	if(strpos(strtolower($_SERVER['HTTP_USER_AGENT']), 'windows phone') !== false)
		$mobile_browser++;
	if($mobile_browser>0)
		return true;
	else
		return false;
}
?>