How to get the HTML for a DOM element in javascript

First, put on element that wraps the div in question, put an id attribute on the element and then use getElementById on it: once you've got the lement, just do 'e.innerHTML` to retrieve the HTML.

<div><span><b>This is in bold</b></span></div>

=> <div id="wrap"><div><span><b>This is in bold</b></span></div></div>

and then:

var e=document.getElementById("wrap");
var content=e.innerHTML;

Note that outerHTML is not cross-browser compatible.

Use outerHTML:

var el = document.getElementById( 'foo' );
alert( el.outerHTML );

Expanding on jldupont's answer, you could create a wrapping element on the fly:

var target = document.getElementById('myElement');
var wrap = document.createElement('div');
wrap.appendChild(target.cloneNode(true));
alert(wrap.innerHTML);

I am cloning the element to avoid having to remove and reinsert the element in the actual document. This might be expensive if the element you wish to print has a very large tree below it, though.