Angular2 i18n language switch
<p>I'm looking for a way to </p>

<ul>
<li>set dynamically the current language to be displayed: I have followed the latest angular cookbook <a href="https://angular.io/docs/ts/latest/cookbook/i18n.html" rel="noreferrer" title="here">here</a> about internationalization 
but it says "<em>the user's language is hardcoded as a global document.locale variable in the index.html</em>"</li>
</ul>

<p>How can this be set dynamically in angular2 + typescript ?</p>

<p>Here is my attempt from the official Angular2 plunkr : <a href="https://plnkr.co/edit/lWV4VhzpWYnCXeDBpzsn?p=preview" rel="noreferrer">https://plnkr.co/edit/lWV4VhzpWYnCXeDBpzsn?p=preview</a>
where I've commented out the </p>

<pre><code>document.locale='en';
</code></pre>

<p>and tried to retrieve the window.document inside a typescript service, and change the locale there, but despite it is called and the locale set properly (seen in the console), the interface is not displayed in the chosen language <strong>at startup</strong>.</p>

<p>Then of course the dropdown buttons don't work either because the same erroneous way is used and the display is not refreshed but that is the next step. </p>