Check if a string contain multiple specific words

Question

How to check, if a string contain multiple specific words?

I can check single words using following code:

$data = "text text text text text text t         


        

Answer 1

if(preg_match('[bad|naughty]', $data) === true) { }

The above is not quite correct.

"preg_match() returns 1 if the pattern matches given subject, 0 if it does not, or FALSE if an error occurred."

So it should be just:

if(preg_match('[bad|naughty]', $data)) { }