is_unique for codeigniter form validation

Question

I'm trying to figure out how I can use the is_unique rule from the Codeigniter form validation library in the following situation.

I'm trying to submit a edit user form and have the rule:

$this->form_validation->set_rules('user_name', 'User Name', 'required|trim|xss_clean|is_unique[users.user_name]'); 

What if other values in the form are being changed but this value stays the same. The form is going to see that this value already exists so how would I protect it from editing if this value isn't changed.

Answer 1

Using your code as an example, the is_unique validation rule works by looking for a field called user_name in your users database table. If the field with the same value exists it validates as false.

To make sure it runs only when the user submits a new value, you could check the posted value $this->input->post('user_name') against the value you pulled from the database to populate your form with. If they are the same, don't validate is_unique;

if($this->input->post('user_name') != $original_value) {    $is_unique =  '|is_unique[users.user_name]' } else {    $is_unique =  '' }  $this->form_validation->set_rules('user_name', 'User Name', 'required|trim|xss_clean'.$is_unique); 

Answer 2

There's a better way to go around it, I think, still using CodeIgniters' validation library... Use edit_unique where you pass an extra parameter which is the id of the row you're editing.. See below.. I use it and works pretty fine for me.. hope it helps

$this->form_validation->set_rules('user_name', 'User Name', 'required|trim|xss_clean|edit_unique[users.user_name.'.$id.']');