Custom Validate Birthday with value for each $year, $month, $day

I solved it thank you for the help! 

This is what I ended up doing with my custom rule:

PHP Code:

public function validateDate($str, string $fields, array $data)
    {
        if (checkdate((int) $data['bday_month'], (int) $data['bday_day'], (int) $data['bday_year'])) {
        
            return TRUE;
    
        } else {

            return FALSE;
        }

    } 


And here is my controller:

PHP Code:

$bday_year = $this->request->getPost('bday_year');
            $bday_month = $this->request->getPost('bday_month');
            $bday_day = $this->request->getPost('bday_day');

            $validation->getRuleGroup('date');
            $validation->setRuleGroup('date');
            $validation->run(['bday_month' => $bday_month, 'bday_day' => $bday_day, 'bday_year' => $bday_year], 'date'); 


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I solved it thank you for the help! 

This is what I ended up doing with my custom rule:

PHP Code:

public function validateDate($str, string $fields, array $data)
    {
        if (checkdate((int) $data['bday_month'], (int) $data['bday_day'], (int) $data['bday_year'])) {
        
            return TRUE;
    
        } else {

            return FALSE;
        }

    } 


And here is my controller:

PHP Code:

$bday_year = $this->request->getPost('bday_year');
            $bday_month = $this->request->getPost('bday_month');
            $bday_day = $this->request->getPost('bday_day');

            $validation->getRuleGroup('date');
            $validation->setRuleGroup('date');
            $validation->run(['bday_month' => $bday_month, 'bday_day' => $bday_day, 'bday_year' => $bday_year], 'date'); 


I also format the date time for use in my views with an entity:

PHP Code:

public function setAge(string $profile)
    {
        $db = \Config\Database::connect();
        $this->builder = $db->table('users');

        $user = $this->userModel->getUser($profile);

        $month = $user->bday_month;
        $day = $user->bday_day;
        $year = $user->bday_year;

        $bday = Time::create($year, $month, $day);

        $this->attributes['age'] = $bday->toDateTimeString();

    }

public function getAge(string $format = 'words')
    {
        if ($format === 'words' && $this->attributes['age'] !== NULL) {

            return $this->attributes['age'] = get_date_words($this->attributes['age']);
        
        } elseif ($format === 'none' && $this->attributes['birthday'] !== NULL) {

            return $this->attributes['age'];
        }
    }