Question

What’s a good way to validate phone numbers being input in codeigniter?

It’s my first time writing an app, and I don’t really understand regex at all.

Is it easier to have three input fields for the phone number?

Answer 1

Here’s a cool regex I found out on the web. It validates a number in almost any US format and converts it to (xxx) xxx-xxxx. I think it’s great because then people can enter any 10 digit US phone number using whatever format they are used to using and you get a correctly formatted number out of it.

Here’s the whole function you can drop into your MY_form_validation class. I wanted my form to allow empty fields so you’ll have to alter it if you want to force a value.

function valid_phone_number_or_empty($value)
{
    $value = trim($value);
    if ($value == '') {
        return TRUE;
    }
    else
    {
        if (preg_match('/^\(?[0-9]{3}\)?[-. ]?[0-9]{3}[-. ]?[0-9]{4}$/', $value))
        {
            return preg_replace('/^\(?([0-9]{3})\)?[-. ]?([0-9]{3})[-. ]?([0-9]{4})$/', '($1) $2-$3', $value);
        }
        else
        {
            return FALSE;
        }
    }
}