php set_rules code example
Example 1: codeigniter form_validation email
$this->form_validation->set_rules('email', 'Email', 'trim|required|valid_email');
Example 2: form validation input inside api codeigniter
$this->form_validation->set_rules('user_api_key', 'User Api Id', 'trim|required');
if ($this->form_validation->run() == FALSE) {
$data = strip_tags($this->form_validation->error_string());
return $this->json_out($data, 0, $code = 'form_validation_error', $msg = 'Some Fields are required');
}