How can I set safe or allow empty captcha on scenario?

Question

I want to set safe or allow empty captcha on scenario like bellow code.

 public function rules() {
        return [
            [['verifyCode'], 'safe', 'on'=>'admin'],
        ];
    }

But it does not work, and I got this error.

Invalid CAPTCHA action ID: site/captcha

and also this page didn't help me.

Answer 1

Try this. Add rule:

[['verifyCode'], 'captcha', 'skipOnEmpty' => true, 'on'=>'admin']

In controller, when create instance:

$model->scenario = 'admin';