PHP Preg_match for a particular symbol

Question

How would you preg_match for the symbol combination |~| or %*|

$harms = 'i.e. flow of electricity in contact with person(s)dsn fds fsdnfsnd fsd fmnds f|~|mnsdf <br /><br />ajshajkhsjkahs|~|';
if(preg_match('#\|~\|#', $harms)) {
echo 'true';
}

Answer 1

You need to escape special chars in RegEx with a backslash \:

preg_match('#\|~\|#', $s);
preg_match('#%\*\|#', $s);

You could also use preg_quote() to escape special chars:

preg_match('#'.preg_quote('|~|%*|','#').'#', $s);