256

I've got 2 ways I can create a <div> using jQuery.

Either:

var div = $("<div></div>");
$("#box").append(div);

Or:

$("#box").append("<div></div>");

What are the drawbacks of using second way other than re-usability?

Cœur
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Ashwin
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8 Answers8

379

The first option gives you more flexibilty:

var $div = $("<div>", {id: "foo", "class": "a"});
$div.click(function(){ /* ... */ });
$("#box").append($div);

And of course .html('*') overrides the content while .append('*') doesn't, but I guess, this wasn't your question.

Another good practice is prefixing your jQuery variables with $:
Is there any specific reason behind using $ with variable in jQuery

Placing quotes around the "class" property name will make it more compatible with less flexible browsers.

Community
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gdoron
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    Also a good practice to start jQuery collection names with a "`$`", in my opinion. Just noting that what you've done does not require `$div`: `$("
    ", {id: 'foo', class: 'a', click: function () {}}).appendTo("#box");`
    – Explosion Pills May 16 '12 at 13:30
  • Are those dollar signs necessary or a typo? `$div`. I haven't seen that syntax before, but I'm new to Jquery. – felwithe Feb 22 '15 at 15:05
  • I always use the $ is the variable is a jquery object, $_ if it is a jQuery collection, and _var if it is a counter. The var for regular variables. – Casey ScriptFu Pharr Oct 23 '15 at 21:33
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    where is the documentation for this way of creating element? `$("
    ", {id: "foo", class: "a"});`. I want to know if there are other options for it
    – Saba Ahang Dec 02 '15 at 21:48
  • @gdoron please, take a look at my question http://stackoverflow.com/questions/35413044/which-is-the-correct-or-better-way-to-create-a-new-element-with-jquery – Vixed Feb 15 '16 at 15:30
  • why is the id key without quotes whereas the class key requires quotes – Jarg7 Jul 21 '18 at 09:01
  • @codemonkey `class` is a reserved keyword in JavaScript while `id` is not. Hence the difference. See http://www.javascripter.net/faq/reserved.htm – gdoron Jul 22 '18 at 18:09
86

I personally think that it's more important for the code to be readable and editable than performant. Whichever one you find easier to look at and it should be the one you choose for above factors. You can write it as:

$('#box').append(
  $('<div/>')
    .attr("id", "newDiv1")
    .addClass("newDiv purple bloated")
    .append("<span/>")
      .text("hello world")
);

And your first Method as:

// create an element with an object literal, defining properties
var $e = $("<div>", {id: "newDiv1", name: 'test', class: "aClass"});
$e.click(function(){ /* ... */ });
// add the element to the body
$("#box").append($e);

But as far as readability goes; the jQuery approach is my favorite. Follow this Helpful jQuery Tricks, Notes, and Best Practices

miken32
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Niranjan Singh
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29

Much more expressive way,

jQuery('<div/>', {
    "id": 'foo',
    "name": 'mainDiv',
    "class": 'wrapper',
    "click": function() {
      jQuery(this).toggleClass("test");
    }}).appendTo('selector');

Reference: Docs

Be sure to read the docs thoroughly, as this notation has certain consequences that won't be immediately obvious to the person inspecting the code.

The name "class" must be quoted in the object since it is a JavaScript reserved word, and "className" cannot be used since it refers to the DOM property, not the attribute. While the second argument is convenient, its flexibility can lead to unintended consequences (e.g. $( "<input>", {size: "4"} ) calling the .size() method instead of setting the size attribute).

toniedzwiedz
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Darshan
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    `class` should be in quotes, according to the docs (via Docs link above): "The name "class" must be quoted in the object since it is a JavaScript reserved word, and "className" cannot be used since it refers to the DOM property, not the attribute." – Isaac Gregson Dec 18 '15 at 20:44
7

According to the jQuery official documentation

To create a HTML element, $("<div/>") or $("<div></div>") is preferred.

Then you can use either appendTo, append, before, after and etc,. to insert the new element to the DOM.

PS: jQuery Version 1.11.x

Alan Dong
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5

According to the documentation for 3.4, It is preferred to use attributes with attr() method.

$('<div></div>').attr(
  {
    id: 'some dynanmic|static id',
    "class": 'some dynanmic|static class'
  }
).click(function() {
  $( "span", this ).addClass( "bar" ); // example from the docs
});
John Henckel
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ymssa___
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0

I would recommend the first option, where you actually build elements using jQuery. the second approach simply sets the innerHTML property of the element to a string, which happens to be HTML, and is more error prone and less flexible.

jbabey
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    @Ash with the second approach, you may mistakenly wipe out all of the other children of the container you are modifying: http://jsfiddle.net/jbabey/RBXq5/1/ – jbabey May 16 '12 at 13:28
0

If #box is empty, nothing, but if it's not these do very different things. The former will add a div as the last child node of #box. The latter completely replaces the contents of #box with a single empty div, text and all.

Explosion Pills
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0

It is also possible to create a div element in the following way:

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

add class

my_div.classList.add('col-10');

also can perform append() and appendChild()

Sнаđошƒаӽ
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