yii2Ajax Request

Submitting Ajax form

View file:
<?php 
use yii;
use yii\bootstrap\ActiveForm;
use yii\helpers\Html;
?>

<?php 
$form = ActiveForm::begin([
    'action' => ['comments/ajax-comment'],
    'options' => [
        'class' => 'comment-form'
    ]
]); 
?>
    <?= $form->field($model, 'comment'); ?>

    <?= Html::submitButton("Submit", ['class' => "btn"]); ?>

<?php ActiveForm::end(); ?>
Javascript:
 jQuery(document).ready(function($) {
       $(".comment-form").submit(function(event) {
            event.preventDefault(); // stopping submitting
            var data = $(this).serializeArray();
            var url = $(this).attr('action');
            $.ajax({
                url: url,
                type: 'post',
                dataType: 'json',
                data: data
            })
            .done(function(response) {
                if (response.data.success == true) {
                    alert("Wow you commented");
                }
            })
            .fail(function() {
                console.log("error");
            });
        
        });
    });
Controller Action:
public function actionAjaxComment()
{
    $model = new Comments();
    if (Yii::$app->request->isAjax) {
        Yii::$app->response->format = \yii\web\Response::FORMAT_JSON;

        if ($model->load(Yii::$app->request->post()) && $model->save()) {
            return [
                'data' => [
                    'success' => true,
                    'model' => $model,
                    'message' => 'Model has been saved.',
                ],
                'code' => 0,
            ];
        } else {
            return [
                'data' => [
                    'success' => false,
                    'model' => null,
                    'message' => 'An error occured.',
                ],
                'code' => 1, // Some semantic codes that you know them for yourself
            ];
        }
    }
}

Render Ajax view

Controller::renderAjax() method can be used to respond to an Ajax request. This method is similar to renderPartial() except that it will inject into the rendering result with JS/CSS scripts and files which are registered with the view

Assume we have login form in a view file:

<?php
use yii\helpers\Html;
use yii\bootstrap\ActiveForm;

\yii\bootstrap\BootstrapAsset::register($this);

<div class="site-login">

    <?php $form = ActiveForm::begin(); ?>

        <?= $form->field($model, 'username')->textInput() ?>

        <?= $form->field($model, 'password')->passwordInput() ?>

        <?= Html::submitButton('Login',['class' => 'btn btn-primary btn-block']) ?>

    <?php ActiveForm::end(); ?>
</div>

When we use renderPartial() in a controller action:

public function actionLogin()
{
    $model = new LoginForm();
    if ($model->load(Yii::$app->request->post()) && $model->login()) {
        return $this->goBack();
    }
    return $this->renderPartial('login', [
        'model' => $model,
    ]);
}

Action output:

<div class="site-login">
    <form id="w0" action="/site/login" method="post" role="form">
        <div class="form-group field-loginform-username required">
            <label class="control-label" for="loginform-username">Имя пользователя</label>
            <input type="text" id="loginform-username" class="form-control" name="LoginForm[username]">
        </div>
        <div class="form-group field-loginform-password required">
            <label class="control-label" for="loginform-password">Пароль</label>
            <input type="password" id="loginform-password" class="form-control" name="LoginForm[password]">
        </div>
        <button type="submit" class="btn btn-primary btn-block">Login</button>
    </form>
</div>

When we use renderAjax() in a controller action:

    ...
    return $this->renderAjax('login', [
        'model' => $model,
    ]);
    ...

Action output (JS,CSS injected):

<link href="/assets/f1759119/css/bootstrap.css" rel="stylesheet">
<div class="site-login">
    <form id="w0" action="/site/login" method="post" role="form">
        <div class="form-group field-loginform-username required">
            <label class="control-label" for="loginform-username">Имя пользователя</label>
            <input type="text" id="loginform-username" class="form-control" name="LoginForm[username]">
        </div>
        <div class="form-group field-loginform-password required">
            <label class="control-label" for="loginform-password">Пароль</label>
            <input type="password" id="loginform-password" class="form-control" name="LoginForm[password]">
        </div>
        <button type="submit" class="btn btn-primary btn-block">Login</button>
    </form>
</div>
<script src="/assets/13aa7b5d/jquery.js"></script>
<script src="/assets/302a2946/yii.js"></script>
<script src="/assets/302a2946/yii.validation.js"></script>
<script src="/assets/302a2946/yii.activeForm.js"></script>

If we want to exclude some assets from view (to prevent dublicates):

...
Yii::$app->assetManager->bundles = [
    'yii\bootstrap\BootstrapAsset' => false,
];
return $this->renderAjax('login', [
    'model' => $model,
]);
...

Action output (no bootstrap.css):

<div class="site-login">
    <form id="w0" action="/site/login" method="post" role="form">
        <div class="form-group field-loginform-username required">
            <label class="control-label" for="loginform-username">Имя пользователя</label>
            <input type="text" id="loginform-username" class="form-control" name="LoginForm[username]">
        </div>
        <div class="form-group field-loginform-password required">
            <label class="control-label" for="loginform-password">Пароль</label>
            <input type="password" id="loginform-password" class="form-control" name="LoginForm[password]">
        </div>
        <button type="submit" class="btn btn-primary btn-block">Login</button>
    </form>
</div>
<script src="/assets/13aa7b5d/jquery.js"></script>
<script src="/assets/302a2946/yii.js"></script>
<script src="/assets/302a2946/yii.validation.js"></script>
<script src="/assets/302a2946/yii.activeForm.js"></script>