Clear ZIP code with Javascript

Question

How to clear the formatting of a zip code field in this format: 87.678-000?

I need to take out the "." and the "-" and return only the numbers. I tried something like, unfortunately it didn’t work.

var i = '^[0-9]+$';
var reg = new RegExp(i);

Answer 1

If all you want is to remove the strokes and dots...

var str = str.replace("-", "").replace(".", "");

Where str is the string with the ZIP code.

If you want to see if a string is a valid zip code, you can use something like:

// força bruta não, força brutíssima! // após 3 edições, já não tão bruta...
var regexp = /\d\d((\d\d\d)|(\.\d\d\d-))\d\d\d/;
var match = str.match(regexp);

Then you check if there was match (if match is null, the string is not a valid ZIP code). This regular expression will take both formatted and unformatted ZIP.

P.S.: I am disregarding whether left zeroes are valid, as I do not know the rules of CEP formation.

Editing: I tweaked the code to make it less gross.

Answer 2

An alternative solution presented by @Renan is to use this regular expression /\.|\-/ to remove the characters . and - string:

var cep = '87.678-000';
cep = cep.replace(/\.|\-/g, '');

alert(cep); // 87678000

Where the modifier /g is used to search for one or more occurrences where . and - is found, of global use.

Demo

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To verify that a CEP is valid(in the format provided by you) could be used something like this:

var cep = '87.678-000';
if (/\d{2}\.\d{3}\-\d{3}/.test(cep))
    alert('Cep é válido!');
else
    alert('Cep inválido!');

Demo

Answer 3

I would like to complement the answer by @Renan with a true CEP validation.

Although the Brazilian CEP is not defined by an algorithm itself but only one structured decimal representation of the country, like any logical structure it follows a standard Valizable by Regular Expressions.

Note that I wrote Regular Expressions, plural, as we have 26 States + one Federal District which, in one structure, result in 27 different patterns.

Years ago, when I was researching for CEP-based auto-fill alternatives, at a "time" when there weren’t many Webservices available and/or trusted, I ended up finding the database itself used by Correios for download in a blog that today no longer exists.

The important thing is that amid the article’s comments there was one of none other than Aurélio Marinho Jargas, author of the best reference book for Regular Expressions in Portuguese.

And in this particular comment he published these 27 Regular Expressions which I quickly tried to implement in PHP. Easy, easy, easy...

Despite the relative difficulty I had in porting the code to Javascript, I did, and leave it as a reference to the community in Jsfiddle.

After the basic length check, first the state is checked by a separate Regular Expression. Only then do we test the first five digits of the zip code, which are the ones that matter against the Regular Expression of the informed State.

All credit goes to Master Aurelius, I just packed everything up like a good Padawan. ^_^