php regex issues

[mschuoi]

I have a pattern match here that looks like it should work fine. However any input I give makes the conditional fail. I will handle the '99999-9999' case after I get the '99999' case working. $ZipCode is a textfield that is being submitted on POST.\[code\]$ZipCode = $_POST["ZipCode"];if(!preg_match("/^[0-9]{5}$/", $ZipCode)){$error_str .= "The zip code you enter must be in the form of: '99999' or '99999-9999'\n";}if(isset($_POST['submit'])){?><script>var error = <?= json_encode($error_str);?>; alert(error); </script><?}\[/code\]'11111' fails and '111111' also fails