Insert sibling node in JS

Question

So I have a div with some pre tags in it, like so:

<div id="editor" >
    <pre contentEditable="true">1</pre>
    <pre contentEditable="true">2</pre>
    <pre contentEditable="true">3</pre>
</div>

Now I want to use Javascript to put a new pre node between 1 and 2. I've been trying to do it this way (since I understand the DOM is a doubly linked tree), but I'm getting the sense that maybe the pointers aren't editable as I'm approaching it.

(just a snippet inside an event handler, e being the event)

var tag = e.srcElement;
    if(tag.nextSibling){
        var next = tag.nextSibling;
        var newPre = document.createElement('pre');
        newPre.setAttribute("contentEditable", "true");
        newPre.innerHTML = "boom";
        tag.nextSibling = newPre;
        newPre.nextSibling = next;
    }

Those last two lines are from my c++ experience, but feel icky in JS. How would I set a new sibling node?

Seedy

Answer 1

Here is how I would do that:

JS

var container = document.getElementById('editor'),
    firstChild = container.childNodes[1];
if (container && firstChild) {
    var newPre = document.createElement('pre');
    newPre.setAttribute("contentEditable", "true");
    newPre.innerHTML = "boom";  
    firstChild.parentNode.insertBefore(newPre, firstChild.nextSibling);    
}

jsfiddle: http://jsfiddle.net/bZGEZ/

Stines

Possible improvements: 1) use 'children' (only elements) instead of 'childNodes' (elements and text nodes); 2) check container's children in 'if': container can be null; 3) use native HTMLElement 'contentEditable' property instead of setAttribute; 4) use 'textContent' instead of 'innerHTML' if you don't require parsing value as HTML (as in this case); 5) use simpler DOM attach methods 'after' and 'before' (most browsers except IE11 support them). – Torbart

Answer 2

You could also insert a new sibling using insertAdjacentElement or insertAdjacentHTML; both of which take the options beforebegin, beforeend, afterbegin and afterend.

Example:

var container = document.getElementById('editor'),
firstChild = container.childNodes[1];

var newPre = document.createElement('pre');
newPre.setAttribute("contentEditable", "true");
newPre.innerHTML = "boom";  
firstChild.insertAdjacentElement("afterend", newPre);

Gambrell

I've been programming for years, and this is the first time I've heard of insertAdjacentElement, and it is absolutely magnificent! Thank you! – Digitalin