TypeScript exports is not defined : <p>I'm trying to use export and import but it not working I get an error</p>

<p>Here is my code HTML :</p>

<pre><code>&lt;!DOCTYPE html&gt;
&lt;html&gt;
&lt;head&gt;
    &lt;meta charset="utf-8" /&gt;
    &lt;meta name="viewport" content="width=device-width, initial-scale=1.0"&gt;
&lt;/head&gt;
&lt;body&gt;
    @RenderBody()

    &lt;script src="~/scripts/user.js"&gt;&lt;/script&gt;
    &lt;script src="~/scripts/main.js"&gt;&lt;/script&gt;
&lt;/body&gt;
&lt;/html&gt;
</code></pre>

<p>User.ts :</p>

<pre><code>export class User {
    firstName: string;
    lastName: string;
}
</code></pre>

<p>main.ts</p>

<pre><code>import { User } from "./user";
</code></pre>

<p>Here is also screenshot of exception :</p>

<p><a href="https://i.stack.imgur.com/9DeNr.png" rel="noreferrer"><img src="https://i.stack.imgur.com/9DeNr.png" alt="enter image description here"></a></p>
