aidehua - 28 January 2010 06:36 PM

Since I can’t find it built in to the form_validation library, I’ve created a MY_form_validation library with a valid_url() function in it:

<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class MY_form_validation extends CI_form_validation {

    function valid_url($str){

           $pattern = "/^(http|https|ftp):\/\/([A-Z0-9][A-Z0-9_-]*(?:\.[A-Z0-9][A-Z0-9_-]*)+):?(\d+)?\/?/i";
            if (!preg_match($pattern, $str))
            {
                return FALSE;
            }

            return TRUE;
    }

} 

Which I call in my validation rules like this:

$this->load->helper('url');
$this->form_validation->set_rules('author_url', 'Website', 'trim|prep_url|valid_url|xss_clean'); 

NB the regex in the valid_url() function requires an http:// or https:// or ftp:// prefix. I’ve added prep_url to the validation rule to add http:// if it is required. That’s why I’ve loaded the URL helper first.

As expected, when validation fails on the author_url field, CodeIgniter displays this message:

The Website field must contain a valid URL

Straight out of the form_validation_lang.php file. Weird that it never made it into the form_validation library.

Its work perfectly for me
i’ve modified more simple

regards and thanks

My solution: I don’t try to check everything.

In my validation rule I simply check for http:// or https:// and for spaces in the url:

At some point, checking everything becomes a pain.

Here is an awesome regex to validate a URL with the added side-benefit of finding the parts of the URL.

It is a built-in regex in a program called RegexBuddy by Just Great Software. That guy is a regex guru. I **highly** recommend it for testing regex expressions in C, PHP, Perl, Java and others.

This one lets you also validate relative URL’s

hugle - 01 November 2009 09:29 AM

Muser - 31 October 2009 08:02 PM

I get the following error:

A PHP Error was encountered

Severity: Warning

Message: preg_match() [function.preg-match]: Unknown modifier ‘|’

Filename: libraries/MY_Form_validation.php

Line Number: 20

can you paste exact function/rule?

I believe you tried to validate an empty string…  You can add this line to the top of the function to check for that:

if( empty($url) ) {
return FALSE;
}