How can I convert an onload promise into Async/Await
<p>I have the following Typescript that I would like to use <code>async</code>/<code>await</code> on.  But I can't seem to sort it out in my head how to do this.</p>

<pre><code>private getWorkbookFromFile2(excelFile: File): Promise&lt;xlsx.IWorkBook&gt; {
    var loadedPromise = new Promise&lt;xlsx.IWorkBook&gt;((resolve, reject) =&gt; {
        var reader = new FileReader();

        reader.onload = (event: any) =&gt; {
            var data = event.target.result;

            var workbook = xlsx.read(data, { type: 'binary' });

            console.log(workbook.SheetNames);
            resolve(workbook);
        };
        reader.readAsBinaryString(excelFile);
    });

    return loadedPromise;
}
</code></pre>

<p>Can someone show me how this Typescript promise can be converted to use <code>async</code>/<code>await</code></p>