PHP - remove HTML tags from string except <img> [closed]

Question

I want to remove all tags except the img tag,

$words = strip_tags($words, '<img>');

Is it useful?

Answer 1

Yes, to remove tags.
But strip_tags() won't help against the most dangerous thing - an XSS. You will need some regular expression, or use http://htmlpurifier.org/ to be sure there are no unwanted parameters in the <img> tag.