スマホで取った写真をプレビュー表示

<!DOCTYPE html>
<html lang="ja">
<head>
<meta charset="utf-8" />
<title>スマホで取った写真をプレビュー表示</title>
<style></style>
<script>
document.addEventListener("DOMContentLoaded", () => {

	document.querySelector("#btnScan").addEventListener("click", function() {
		document.querySelector("#fulImage").click();
	});

	document.querySelector("#fulImage").addEventListener("change", function(e) {
		var reader = new FileReader();
		reader.onload = function (e) {
			document.querySelector("#imgPhoto").src = e.target.result;
		};
		reader.readAsDataURL(e.target.files[0]);
	});

});
</script>
</head>
<body>

<div><img id="imgPhoto" width="300" height="300"><div>

<div>
	<input type="file" id="fulImage" style="display:none">
	<button id="btnScan">scan</button>
</div>

</body>
</html>