I'm refactoring some old JavaScript code and there's a lot of DOM manipulation going on.
var d = document;
var odv = d.createElement("div");
odv.style.display = "none";
this.OuterDiv = odv;
var t = d.createElement("table");
t.cellSpacing = 0;
t.className = "text";
odv.appendChild(t);
I would like to know if there is a better way to do this using jQuery. I've been experimenting with:
var odv = $.create("div");
$.append(odv);
// And many more
But I'm not sure if this is any better.
Here's your example in the "one" line.
this.$OuterDiv = $('<div></div>')
.hide()
.append($('<table></table>')
.attr({ cellSpacing : 0 })
.addClass("text")
)
;
Update: I thought I'd update this post since it still gets quite a bit of traffic. In the comments below there's some discussion about $("<div>")
vs $("<div></div>")
vs $(document.createElement('div'))
as a way of creating new elements, and which is "best".
I put together a small benchmark, and here are roughly the results of repeating the above options 100,000 times:
jQuery 1.4, 1.5, 1.6
Chrome 11 Firefox 4 IE9
<div> 440ms 640ms 460ms
<div></div> 420ms 650ms 480ms
createElement 100ms 180ms 300ms
jQuery 1.3
Chrome 11
<div> 770ms
<div></div> 3800ms
createElement 100ms
jQuery 1.2
Chrome 11
<div> 3500ms
<div></div> 3500ms
createElement 100ms
I think it's no big surprise, but document.createElement
is the fastest method. Of course, before you go off and start refactoring your entire codebase, remember that the differences we're talking about here (in all but the archaic versions of jQuery) equate to about an extra 3 milliseconds per thousand elements.
Update 2
Updated for jQuery 1.7.2 and put the benchmark on JSBen.ch
which is probably a bit more scientific than my primitive benchmarks, plus it can be crowdsourced now!
Simply supplying the HTML of elements you want to add to a jQuery constructor $()
will return a jQuery object from newly built HTML, suitable for being appended into the DOM using jQuery's append()
method.
For example:
var t = $("<table cellspacing='0' class='text'></table>");
$.append(t);
You could then populate this table programmatically, if you wished.
This gives you the ability to specify any arbitrary HTML you like, including class names or other attributes, which you might find more concise than using createElement
and then setting attributes like cellSpacing
and className
via JS.
Creating new DOM elements is a core feature of the jQuery()
method, see:
http://api.jquery.com/jQuery/#creating-new-elements
and particulary http://api.jquery.com/jQuery/#example-1-1
I'm doing like that:
$('<div/>',{
text: 'Div text',
class: 'className'
}).appendTo('#parentDiv');
since jQuery1.8
, using $.parseHTML()
to create elements is a better choice.
there are two benefits:
1.if you use the old way, which may be something like $(string)
, jQuery will examine the string to make sure you want to select a html tag or create a new element. By using $.parseHTML()
, you tell jQuery that you want to create a new element explicitly, so the performance may be a little better.
2.much more important thing is that you may suffer from cross site attack (more info) if you use the old way. if you have something like:
var userInput = window.prompt("please enter selector");
$(userInput).hide();
a bad guy can input <script src="xss-attach.js"></script>
to tease you. fortunately, $.parseHTML()
avoid this embarrassment for you:
var a = $('<div>')
// a is [<div></div>]
var b = $.parseHTML('<div>')
// b is [<div></div>]
$('<script src="xss-attach.js"></script>')
// jQuery returns [<script src="xss-attach.js"></script>]
$.parseHTML('<script src="xss-attach.js"></script>')
// jQuery returns []
However, please notice that a
is a jQuery object while b
is a html element:
a.html('123')
// [<div>123</div>]
b.html('123')
// TypeError: Object [object HTMLDivElement] has no method 'html'
$(b).html('123')
// [<div>123</div>]
parseHTML
is good for html coming from external sources, but that "all the boost is gone after wrapping the results in a new jQuery object". That is, if you want to hard-code the creation of a new jQuery-wrapped html element, $("<div>stuff</div>")
style still seems to win.
UPDATE
As of the latest versions of jQuery, the following method doesn't assign properties passed in the second Object
Previous answer
I feel using document.createElement('div')
together with jQuery
is faster:
$(document.createElement('div'), {
text: 'Div text',
'class': 'className'
}).appendTo('#parentDiv');
Though this is a very old question, I thought it would be nice to update it with recent information;
Since jQuery 1.8 there is a jQuery.parseHTML() function which is now a preferred way of creating elements. Also, there are some issues with parsing HTML via $('(html code goes here)')
, fo example official jQuery website mentions the following in one of their release notes:
Relaxed HTML parsing: You can once again have leading spaces or newlines before tags in $(htmlString). We still strongly advise that you use $.parseHTML() when parsing HTML obtained from external sources, and may be making further changes to HTML parsing in the future.
To relate to the actual question, provided example could be translated to:
this.$OuterDiv = $($.parseHTML('<div></div>'))
.hide()
.append($($.parseHTML('<table></table>'))
.attr({ cellSpacing : 0 })
.addClass("text")
)
;
which is unfortunately less convenient than using just $()
, but it gives you more control, for example you may choose to exclude script tags (it will leave inline scripts like onclick
though):
> $.parseHTML('<div onclick="a"></div><script></script>')
[<div onclick="a"></div>]
> $.parseHTML('<div onclick="a"></div><script></script>', document, true)
[<div onclick="a"></div>, <script></script>]
Also, here's a benchmark from the top answer adjusted to the new reality:
jQuery 1.9.1
$.parseHTML: 88ms $($.parseHTML): 240ms <div></div>: 138ms <div>: 143ms createElement: 64ms
It looks like parseHTML
is much closer to createElement
than $()
, but all the boost is gone after wrapping the results in a new jQuery object
var mydiv = $('<div />') // also works
var div = $('<div/>');
div.append('Hello World!');
Is the shortest/easiest way to create a DIV element in jQuery.
I've just made a small jQuery plugin for that: https://github.com/ern0/jquery.create
It follows your syntax:
var myDiv = $.create("div");
DOM node ID can be specified as second parameter:
var secondItem = $.create("div","item2");
Is it serious? No. But this syntax is better than $("
"), and it's a very good value for that money.I'm a new jQuery user, switching from DOMAssistant, which has a similar function: http://www.domassistant.com/documentation/DOMAssistantContent-module.php
My plugin is simpler, I think attrs and content is better to add by chaining methods:
$("#container").append( $.create("div").addClass("box").html("Hello, world!") );
Also, it's a good example for a simple jQuery-plugin (the 100th one).
It's all pretty straight forward! Heres a couple quick examples...
var $example = $( XMLDocRoot );
var $element = $( $example[0].createElement('tag') );
// Note the [0], which is the root
$element.attr({
id: '1',
hello: 'world'
});
var $example.find('parent > child').append( $element );
Not mentioned in previous answers, so I'm adding working example how to create element elements with latest jQuery, also with additional attributes like content, class, or onclick callback:
const mountpoint = 'https://jsonplaceholder.typicode.com/users' const $button = $('button') const $tbody = $('tbody') const loadAndRender = () => { $.getJSON(mountpoint).then(data => { $.each(data, (index, { id, username, name, email }) => { let row = $('
ID | Username |
---|
What about this, for example when you want to add a <option>
element inside a <select>
$('<option/>')
.val(optionVal)
.text('some option')
.appendTo('#mySelect')
You can obviously apply to any element
$('<div/>')
.css('border-color', red)
.text('some text')
.appendTo('#parentDiv')
jQuery out of the box doesn't have the equivalent of a createElement. In fact the majority of jQuery's work is done internally using innerHTML over pure DOM manipulation. As Adam mentioned above this is how you can achieve similar results.
There are also plugins available that make use of the DOM over innerHTML like appendDOM, DOMEC and FlyDOM just to name a few. Performance wise the native jquery is still the most performant (mainly becasue it uses innerHTML)
Success story sharing
JSBen.ch
doesn't show any time, which I would expect in a benchmark. Am I wrong?