PHP防止JS注入正则

 $a ="/]*?>.*?/si";
 $keyword = preg_replace($a,' ',$_POST['searchword']);

$title="";
$title = strip_tags($title);
if(preg_match('/||/',$title,$info)){
 $title=$info['1'];
}else{
 $title = $title;
}
echo $title;