One paragraph description and one code snippet to clarify usage of yii\web\View::render() in a view context, as using echo is a significant change from partial view usage in Yii 1.1.
Currently `Yii::$app->log` is not the `yii\log\Logger`, but the `yii\log\Dispatcher`. Logger is transient component used indirectly and separately by the dispatcher and helper methods for logging.
1. UploadedFile::getInstances($model, 'file'); sees only one file if not set ```'file[]'```
```php
<?= $form->field($model, 'file[]')->fileInput(['multiple' => '']) ?>
```
2. ```$form->errorSummary(..)``` not return all errors of file attribute, but only the last.
So I had to invent.
```php
if ($model->hasErrors()) {
echo '<pre>';
print_r($model->getErrors());
echo '</pre>';
}
```
So it should be?
It is a issue i found when I translate it.
> Composer is not a package manager, It's a tool for dependency management.
According to their [doc](https://getcomposer.org/doc/00-intro.md)
>Composer is a tool for dependency management in PHP. It allows you to declare the dependent libraries your project needs and it will install them in your project for you.
and
> **Composer is not a package manager.** Yes, it deals with "packages" or libraries, but it manages > them on a per-project basis, installing them in a directory (e.g. vendor) inside your project. By > default it will never install anything globally. Thus, it is a dependency manager.
So i think, It will be better, if we remain their offical appellation.