Use getElementById on newly created DOM object before it is inserted into the document -- HOW?

The getElementById method cannot be used unless the DOM element is attached to the document. By what method or mechanism can I access and modify a DOM element before it is attached to the document?

I have a large DOM element and I want to access a piece of it. I would classically use getElementById, but the DOM element is not attached to the document.

var element = document.createElement("div");  
element.id = 'testqq';  
var el = document.getElementById('testqq'); // el will be null!

source: https://developer.mozilla.org/en/dom/document.getelementbyid

I am looking for an answer that does not use jQuery. I love开发者_运维百科 jQuery, but it is not an option for my current problem.

Well, you already have a reference to it with your element variable.

But I'll bet you mean you want something nested inside. If that's right, you could use getElementsByTagName('*'), then iterate over the collection that's returned, testing the ID property until yours is found.

var div = document.createElement('div');

div.innerHTML = '<p>yo</p><div><span id="tester">hi</span></div>';

var all = div.getElementsByTagName('*');

   // search for element where ID is "tester"
for (var i = 0, len = all.length; i < len; i++) {
    if (all[i].id === 'tester') {
        var result = all[i];
        break;
    }
}

alert( result.id );

Before you try the loop, you can test to see if querySelectorAll is supported in the browser, and use that if so.

if( div.querySelectorAll ) {
    var result = div.querySelectorAll('#tester');
} else {
    // Do the loop with getElementsByTagName()
}

The document.createElement function returns a new element object, but that element doesn't exist in the DOM until you insert it.

The document object has no recollection of elements you asked it to create, so when you call document.getElementById('testqq'), it has absolutely no idea what you're looking for.

In your example, you have a reference to the element already. Why do you need to ask the document for it?