Detailed explanation of how PHP determines whether it is a WAP mobile client

// If there is HTTP_X_WAP_PROFILE, it must be a mobile device
if (isset($_SERVER['HTTP_X_WAP_PROFILE'])) {
return true;
}

Analysis : By getting the HTTP_X_WAP_PROFILE information returned by the client, it can be judged that it must be a mobile terminal, but not all mobile phones can return this information. This is the same as getting via later, which involves issues with the terminal and the service provider! Code:

//If the via information contains wap, it must be a mobile device. Some service providers will block this information
if(isset($_SERVER['HTTP_VIA']))
{
//Find If not, it is false, otherwise it is true
return stristr($_SERVER['HTTP_VIA'], "wap") ? true : false;
}

Analysis: This HTTP_VIA contains some personal information provided by the service provider. It is the most accurate to judge based on this, but for example, China Mobile has blocked this information. Therefore, it is only valid for some service providers. Code:

//Brainless method to determine the client flag sent by the mobile phone. The compatibility needs to be improved
if(isset($_SERVER['HTTP_USER_AGENT']))
{
$clientkeywords = array( 'nokia','sony','ericsson','mot','samsung',
'htc','sgh','lg','sharp','sie-','philips','panasonic', 'alcatel',
'lenovo','iphone','ipod','blackberry','meizu','android','netfront',
'symbian','ucweb','windowsce','palm', 'operamini','operamobi',
'openwave','nexusone','cldc','midp','wap','mobile');
// Find keywords for mobile browsers from HTTP_USER_AGENT
if ( preg_match("/(".implode('|',$clientkeywords).")/i",
strtolower($_SERVER['HTTP_USER_AGENT'])))
{
return true;
}
}

analysis: This configures the mobile terminal keyword by returning information [HTTP_USER_AGENT] from the client. Just imagine, you need to list all the mobile phone logos to accurately judge. Is this feasible? Therefore, as long as you list the mainstream mobile phone brands, it will basically be OK. However, one of the above codes is to judge ucweb, which cannot be judged.

Because, the information I obtained is consistent with the information obtained from firefox, and I can’t find the ucweb keyword. Therefore, it is impossible to judge using the ucweb browser, waiting for new methods to emerge. After all, ucweb accounts for the vast majority of users, but ucweb is based on PC browser standards, so it’s okay to be mistaken for a PC browser! Code:

//Protocol method, because it may be inaccurate, leave it to the final judgment
if (isset($_SERVER['HTTP_ACCEPT'])) {
//If only wml is supported and not If it supports html, it must be a mobile device
// If it supports wml and html but wml comes before html, it is a mobile device
if ((strpos($_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;
}
}

Analysis: In the end, it’s an agreement, and it’s not an agreement at all. It is mime type judgment. It goes without saying that a mobile phone that only receives wml pages must be a mobile terminal, but such a naive idea is impossible. Because now mobile phones are gradually becoming close to the functions of computers! ? The acceptable page types on the browser are not just wml, html is also supported. Receiving wml is ranked ahead of html. This can be said to be a mobile phone, but it is not absolute. For example, in Blueberry, html is ranked first and wml is ranked last. This makes it impossible to make a judgment.

To sum up, write the following PHP judgment page program.

/**
*Program: iswap.php determines whether it is accessed through a mobile phone
*Program returns: @return bool whether it is a mobile device
*/
function isMobile()
{
// If there is HTTP_X_WAP_PROFILE, it must be a mobile device
if (isset($_SERVER['HTTP_X_WAP_PROFILE']) ) {
return true;
}

//If the via information contains wap, it must be a mobile device. Some service providers will block this information
if(isset($_SERVER['HTTP_VIA']))
{
//Can't find it to false, otherwise true
return stristr($_SERVER['HTTP_VIA'],"wap") ? true : false;
}

//Brainless method, judge the client flag sent by the mobile phone, compatibility needs to be improved
 if(isset($_SERVER['HTTP_USER_AGENT']))
{
$clientkeywords = array('nokia','sony','ericsson','mot','samsung',
'htc','sgh', 'lg','sharp','sie-','philips','panasonic','alcatel',
'lenovo','iphone','ipod','blackberry','meizu','android', 'netfront',
'symbian','ucweb','windowsce','palm','operamini','operamobi',
'openwave','nexusone','cldc','midp','wap', 'mobile');
// Find keywords for mobile browsers from HTTP_USER_AGENT
if (preg_match("/(".implode('|',$clientkeywords).")/i",
strtolower($_SERVER[ 'HTTP_USER_AGENT'])))
{
return true;
}
}

//Protocol method, because it may be inaccurate, leave it to the final judgment
if (isset($_SERVER['HTTP_ACCEPT'])) {
 // If it only supports wml and not html, it must be a mobile device
// If it supports wml and html but wml comes before html, it is a mobile device
if ((strpos($_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;
}
?>