What is the best way to inject HTML into the DOM with jQuery?

Will Morgan picture Will Morgan · Jun 23, 2009 · Viewed 12.9k times · Source

I'm working on a calendar page that allows a user to click on a day, and enter an entry for that day with a form that pops up.

I'm no stranger to DOM manipulation with jQuery, but this is something I've done before and I'm beginning to wonder if there's a more efficient way to do this?

Would building the HTML manually within JavaScript be the most efficient way performancewise (I assume this is true, over using functions like appendTo() etc) or would creating a hidden construct within the DOM and then cloning it be better?

Ideally I want to know the optimal method of doing this to provide a balance between code neatness and performance.

Thanks,

Will

Answer

James picture James · Jun 23, 2009

Working with huge chunks of HTML strings in JavaScript can become very ugly very quickly. For this reason it might be worth considering a JavaScript "template engine". They needn't be complicated - Check out this one by Resig.

If you're not up for that then it's probably fine to just continue as you are. Just remember that DOM manipulation is generally quite slow when compared to string manipulation.

An example of this performance gap:

// DOM manipulation... slow
var items = ['list item 1', 'list item 2', 'list item 3'];
var UL = $('<ul/>');
$.each(items, function(){
    UL.append('<li>' + this + '</li>');
});

// String manipulation...fast
var items = ['list item 1', 'list item 2', 'list item 3'];
var UL = $('<ul/>').append( '<li>' + items.join('</li><li>') + '</li>' );