Yii2.0 registration verification model and view method call

View signup.php code:

<?php use yii\helpers\Html; use yii\bootstrap\ActiveForm; 
/* @var $this yii\web\View */ /* @var $form yii\bootstrap\ActiveForm */ /* @var $model \frontend\models\SignupForm */ $this->title = &#39;注册&#39;; $this->params[&#39;breadcrumbs&#39;][] = $this->title; ?> <div class="site-signup">
    <h1><?= Html::encode($this->title) ?></h1>
    <p>Please fill out the following fields to signup:</p>
    <div class="row">
        <div class="col-lg-5">
            <?php $form = ActiveForm::begin([
                &#39;id&#39; => &#39;form-signup&#39;,
                &#39;enableAjaxValidation&#39; => true,
                &#39;enableClientValidation&#39; => true,
            ]); ?>
                
                <?= $form->field($model, &#39;username&#39;) ?>
                <?= $form->field($model, &#39;email&#39;) ?>
                <?= $form->field($model, &#39;password&#39;)->passwordInput() ?>
                <?= $form->field($model, &#39;password_compare&#39;)->passwordInput() ?>
                
                <div class="form-group">
                    <?= Html::submitButton(&#39;Signup&#39;, [&#39;class&#39; => &#39;btn btn-primary&#39;, &#39;name&#39; => &#39;signup-button&#39;]) ?>
                </div>
                
            <?php ActiveForm::end(); ?>
        </div>
    </div>
</div>

Controller SiteController.php

public function actionSignup() { $model = new SignupForm(); $model->load($_POST); if (Yii::$app->request->isAjax) {
            Yii::$app->response->format = \yii\web\Response::FORMAT_JSON; return \yii\bootstrap\ActiveForm::validate($model);
        } if ($model->load(Yii::$app->request->post())) { if ($user = $model->signup()) { if (Yii::$app->getUser()->login($user)) { return $this->goHome();
                }
            }
        } return $this->render('signup', [ 'model' => $model,
        ]);
    }

Model SignupForm.php

use common\models\User; use yii\base\Model; use Yii; /**
 * Signup form
 */ class SignupForm extends Model { public $username; public $email; public $password; public $password_compare; /**
     * @inheritdoc */ public function rules() { return [
            ['username', 'filter', 'filter' => 'trim'],
            ['username', 'required'],
            ['username', 'unique', 'targetClass' => '\common\models\User', 'message' => '用户名已存在.'],
            ['username', 'string', 'min' => 2, 'max' => 255],
            ['email', 'filter', 'filter' => 'trim'],
            ['email', 'required'],
            ['email', 'email'],
            ['email', 'unique', 'targetClass' => '\common\models\User', 'message' => '邮箱名已存在.'],
            [['password', 'password_compare'], 'required'],
            [['password', 'password_compare'], 'string', 'min' => 6, 'max' => 16, 'message' => '{attribute}是6-16位数字或字母'],
            ['password_compare', 'compare', 'compareAttribute' => 'password', 'message' => '两次密码不一致'],
        ];
    } /**
     * Signs user up.
     *
     * @return User|null the saved model or null if saving fails
     */ public function signup() { 
     if ($this->validate()) { 
        $user = new User(); $user->username = $this->username; $user->email = $this->email; $user->setPassword($this->password); $user->generateAuthKey(); if ($user->save()) { 
        return $user;
            }
        } return null;
    }
}