Preserved Topic: another JS RegExp problem (Page 1 of 1)

Hi everyone. I'm trying to test to see if a user has entered a correct zip code in a form. I'm getting wierd errors and I don't know why.

The code:

var pattern = /\d{5}/;
if (pattern.test(element.value)) {
alert(element.value);
return true;
}
else { return false; }

What is happening is that it matches 5 or more digits, not exactly 5. I have tried using the pattern /\d\d\d\d\d/ but the same thing happens.
I have tried changing my language declaration in the script tag to include the version number, but that didn't seem to help either.
The alert was put in to double check the element's value, and it returns whatever I entered in the field, no mistakes there.
I know I can test for string length to fix this probelm, but it seems like I shouldn't have to do so.

Am I missing something obvious? Or is this some kind of bug. BTW, I'm testing this using IE 5.5.

Thanks in advance,
Cira

The problem is that the following string:

"123456789"

*does* contain five digits in a row. For example, it contains "12345" which matches the pattern, and it contains "34567" which matches the pattern.

You need to set your pattern so that it requires the five digits to start at the beginning of the string and end at the end of the string. The pattern

/^\d{5}$/

Should work, if I remember correctly. ^ matches the beginning of the string, and $ matches the end.

wonderful, thank you for your help. I assumed I was missing something as I am new to regular expression.

-Cira

um... I'm not gonna knock you for using regexp's (and learning them it's a great skill, kinda like SQL that you use with virtually all languages).

but in a simple case like this just testing the length

if (element.length.value == 5)

is fine.
if it were an email address you were testing for however



.:[ Never resist a perfect moment ]:.

Well, a reg exp is also able to make sure that they're all digits simultaneously.

regexes are the future of all computing! okay, maybe not, but for field validation (i.e. string parsing), there's nothing better. how long would the code be to test for an extended ZIP code? well, my regex is simple:

/^\d{5}(-?\d{4})?$/

once you learn regexes, you'll be hard-pressed to try thinking about these kinds of problems in another light. IMHO, regexes are what make Perl so strong.

Of course, even those RegExp's won't keep me from entering "00000" as my zip code, which is what I always do =)

Keep in mind that many contries don't have zip codes, so don't require them if you want your page to work everywhere.

What you are proving by entering 00000 is that there is no substitute for server-side validation. Too often I have come across applications in a production environment that rely solely on client-side validation.