判断是否是通过手机访问

/**
*判断是否是通过手机访问
*/
if(!function_exists('isMobile'))
{
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;
}
}

//获得当前的页面文件的url
if(!function_exists('GetCurUrl'))
{
function GetCurUrl()
{
if(!empty($_SERVER['REQUEST_URI']))
{
$nowurls = explode('?',$_SERVER['REQUEST_URI']);
$nowurl = $nowurls[0];
}
else
{
$nowurl = $_SERVER['PHP_SELF'];
}

return $nowurl;
}
}

//判断访问设备
if(IsMobile() && !strstr(GetCurUrl(),'3g.php'))
{
header('location:3g.php');
}