Ajax :: Parse A HTML String Received From A Request?

I need to parse an HTML string received from an AJAX request. I wrote a function that places the HTML string into an unappended (not added) <div> , which opens the string up to the DOM hierarchy. However, when I try to access the elements of this <div> , I get an error in the console that says root.getElementById is not a function. This tells me that I can't access any of the child nodes.

Here is what my script looks like:

function parseHTML(html) {
var root = document.createElement("div");
root.innerHTML = html;
// The error console stops at this line

[Code]...