creating custom callback validation rule in codeigniter 2.x - php

Question

how can I create custom validation rule in codeigniter 2.x which can be commonly used throughout application?
I know we can create callback functions in controller, which can then be used in validation rule as -
$this->form_validation->set_rules('user_dob', 'Date of Birth', 'required|callback_validDate|callback_validAge');
And now we can create validation function in controller as -
public function validDate($date) {
$d = DateTime::createFromFormat('d-M-Y', $date);
if ($d && $d->format('d-M-Y') == $date)
return TRUE;
$this->form_validation->set_message('validDate', ' %s is not in correct date format');
return FALSE;
}
But there is a limitation. I can use this method only inside that particular controller. This function can't be used for other controllers. I will have to write the same code again.
For this I tried creating helper file with the given validation function, but again no luck.
So how can I use validation function many times, created once at a common file in codeigniter ?

Answer 1

I too faced the same problem. So I came across a solution for creating validation function, common all around the controller.
Create a file MY_Form_validation.php in the directory /application/libraries/ with following code -
<?php
if (!defined('BASEPATH'))
exit('No direct script access allowed');
class MY_Form_validation extends CI_Form_validation {
protected $CI;
function __construct() {
parent::__construct();
$this->CI = & get_instance();
}
function validDate($date) {
$this->CI->form_validation->set_message('validDate', ' %s is not in correct date format');
$d = DateTime::createFromFormat('d-M-Y', $date);
if ($d && $d->format('d-M-Y') == $date)
return TRUE;
return FALSE;
}
}
Now in your controller, you can use the function name as new rule as -
$this->form_validation->set_rules('user_dob', 'Date of Birth', 'required|validDate|validAge');
And if required you can load library in constructor of controller as -
$this->load->library('form_validation');
For further information you can refer to the link -https://arjunphp.com/custom-validation-rules-codeigniter/