How to add print button for an image?

Codes:

<img id=”print-img” src=”Image URL”>

<a id=”img-print-btn-width” onclick=”myApp.printImage()”>Print Calendar <i class=”fa fa-print” aria-hidden=”true”></i></a>

<style>
#img-print-btn {
padding: 8px 15px;
font-size: 15px;
color: #fff;
background: linear-gradient(180deg,#11aff7 0%,#0b8ed1 100%);
margin: auto;
text-align: center;
cursor: pointer;
}
</style>

<script>
var myApp = new function () {
this.printImage = function () {
var tab = document.getElementById(‘print-img’);
var win = window.open(”, ”, ‘height=700,width=700’);
win.document.write(tab.outerHTML);
win.document.close();
win.print();
}
}
</script>