I am using this preg_match string
preg_match
preg_match(\'/Trident/7.0; rv:11.0/\',$_SERVER[\"HTTP_USER_AGENT\"]
to detect IE11 so I can
I think it should be
if (preg_match("/Trident\/7.0;(.*)rv:11.0/", $_SERVER["HTTP_USER_AGENT"], $match) != 0) {}
because sometimes you can see the user agent like this one
Mozilla/5.0 (Windows NT 6.3; WOW64; Trident/7.0; ASU2JS; rv:11.0) like Gecko