Form submit in EJ2 TypeScript List box control

In the following code snippet, the value that is in selected state will be sent on form submit.

import { ListBox } from '@syncfusion/ej2-dropdowns';
import { Button } from '@syncfusion/ej2-buttons';

// define the array of object
let data: { [key: string]: Object }[] = [
    { text: 'Hennessey Venom' },
    { text: 'Bugatti Chiron' },
    { text: 'Bugatti Veyron Super Sport' },
    { text: 'SSC Ultimate Aero' },
    { text: 'Koenigsegg CCR' },
    { text: 'McLaren F1' },
    { text: 'Aston Martin One- 77' },
    { text: 'Jaguar XJ220' },
    { text: 'McLaren P1' },
    { text: 'Ferrari LaFerrari' },
];

// initialize ListBox component
let listObj: ListBox = new ListBox({
    //set the data to dataSource property
    dataSource: data
});
listObj.appendTo('#listbox');

let button: Button = new Button({ isPrimary: true, content: 'Submit' });
button.appendTo('#btnElement');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 ListBox</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Typescript UI Controls" />
    <meta name="author" content="Syncfusion" />
    <link href="styles.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-dropdowns/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-buttons/styles/material.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>LOADING....</div>
    <div id='container' style="margin:0 auto; width:250px;">
        <form>
            <!--element which is going to render the ListBox-->
            <input id='listbox' />
            <button id="btnElement"></button>
        </form>
    </div>
</body>

</html>