iframe onload with src not working in IE11

Question

I have a JavaScript program that gets the last modified date of a txt file. The code works fine in Firefox but for some reason, it does nothing in IE11. My code is listed below.

JavaScript code:

function getLastMod(){
    var myFrm = document.getElementById('myIframe');
    var lastMod = new Date(myFrm.contentWindow.document.lastModified);
    var getSpan = document.getElementById('LastModified');
    getSpan.innerHTML += "<font color=red> (File Last Updated: " + lastMod.toLocaleString() + ")</font>";
}

HTML code:

<span id="LastModified"></span>
<iframe id="myIframe" onload="getLastMod()" src="date.txt" style="display:none;"></iframe>

Answer 1

I had a similar issue when I tried to define the event in the tag. I had better results assigning the event from within javascript.

<script type="text/javascript">
    document.getElementById('myIframe').onload = function() {
        getLastMod();
    }
</script>