ResponseString from XMLHttpRequest displays in alert but not in div

So I'm new and trying to display the output of a request as a div using the codes below:

<div id="myDiv"></div>
<button onclick="myFunction()">Try it</button> //button to test requeststring in alert box

<script>
function createCORSRequest(method, url){
  var xhr = new XMLHttpRequest();
  if ("withCredentials" in xhr){
    xhr.open(method, url, true);
  } else if (typeof XDomainRequest != "undefined"){
    xhr = new XDomainRequest();
    xhr.open(method, url);
  } else {
    xhr = null;
  }
  xhr.send();
  return xhr;
}

var url = 'http://ift.tt/1D59bUX;
var xhr = createCORSRequest('GET', url);

document.getElementById("myDiv").innerHTML=xhr.responseText;

function myFunction() {
    alert(document.getElementById(xhr.responseText);
}
</script>

The alert correctly display the responseText when a test button is clicked. However. I cannot display this text in my div using the document.getElementById("myDiv").innerHTML=xhr.responseText; line? Any solutions to do the latter?