How to list all directories in Yii2
<p>How can I list all <strong>directories</strong> in Yii2?</p>

<p>I know there is a <a href="http://www.yiiframework.com/doc-2.0/yii-helpers-filehelper.html" rel="nofollow noreferrer"><code>FileHelper</code></a> to list all files in a directory/subdirectory, but I could not list directory using that.</p>

<p>Of course I can use raw PHP to do this, but before that I want to check if Yii2 provides any sort of functionality for it.</p>