【www.gdgbn.com--浏览器】

function browsers(){
   global $HTTP_USER_AGENT ;
   if (isset($HTTP_USER_AGENT)){
    $sAgent = $HTTP_USER_AGENT;
   }else{
    $sAgent = $_SERVER["HTTP_USER_AGENT"];
   }
   if (strpos($sAgent,"MSIE") !== false && strpos($sAgent,"mac") === false && strpos($sAgent,"Opera") === false){
    $iVersion = (float)substr($sAgent,strpos($sAgent,"MSIE") + 5,3);
    return ($iVersion >= 5.5) ;
   }else if (strpos($sAgent,"Gecko/") !== false){
    $iVersion = (int)substr($sAgent,strpos($sAgent,"Gecko/") + 6,8);
    return ($iVersion >= 20030210) ;
   }else{
    return false;
   }
  }

本文来源：http://www.gdgbn.com/bangongshuma/20676/