A model uses the yii\base\Model::$scenario property for the ‘Scenario’ concept. By default, a model supports only a single scenario named default.

Yii2.0 framework model is designed in very comfortable way for dynamic logic based on scenario. In this tutorial i will share my experience about ‘Scenarios’. A model may be used in different scenarios in different business rules and logic.

For example, when we register a user we will get username, password and email. At the same time during the user login, we will get username and password only. One model expecting different type of validation. But we can handle this easily using yii2.0 scenario.

User Register Scenario - Required - username, password, email
User Login Scenario - Required - username, email

Create Scenario For Model In Yii2.0


<?php
class User extends Model
{
    public $name;
    public $email;
    public $password;	
    public function rules(){
        return [
	    [['name','email','password'],'required'],
	    ['email','email'],
	    [['name', 'email', 'password'], 'required', 'on' => 'register'],
        ];
    }
    public function scenarios() {
        $scenarios = parent::scenarios();
        $scenarios['login'] = ['name','password'];//Scenario Values Only Accepted
	return $scenarios;
    }
}
?>

Apply Scenario For Model In Yii2.0

See the below code, We added two ways of setting the scenario of a model. By default, scenario will support the model rules.


<?php
...
class UserController extends Controller
{
    ..
    // APPLY SCENARIOS
    // scenario is set as a property
    ............
    public function  actionLogin(){
    	$model = new User;
	$model->scenario = 'login';
	.............
    }
    // scenario is set through configuration
    public function  actionRegister(){
	$model = new User(['scenario' => 'register']);
	..............
    }
}
?>