js-emoji - Display emoji in the browser, everywhere

Recent OSX and iOS versions allow display and input of emoji. It's nice to show them on other devices too, and the browser is a good place to do it. This library converts emoji (either from character codes or colon-sequences like :smile:) into something that will work on the host computer - either native character codes, a CSS styled span or a text representation.

Usage

<link href="emoji.css" rel="stylesheet" type="text/css" />
<script src="emoji.js" type="text/javascript"></script>
<script type="text/javascript">

// replaces \u{1F604} with platform appropriate content
var output1 = emoji.replace_unified(input);

// replaces :smile: with platform appropriate content
var output2 = emoji.replace_colons(input);

// force text output mode
emoji.text_mode = true;

// show the short-name as a `title` attribute for css/img emoji
emoji.include_title = true;

// change the path to your emoji images (requires trailing slash)
// you can grab the images from here:
// https://github.com/github/gemoji/tree/master/images/emoji/unicode
emoji.img_path = "http://my-cdn.com/images/emoji/";

// find out the auto-detected mode
alert(emoji.replace_mode);

</script>

You can view a live demo here.

Lifecycle

The library is designed to be used with the following flow:

1. User enters text on an iPhone/iPod, Mac running OSX Lion or Android phone
2. Within that text, user enters some emoji
3. Data is stored by application, optionally translated to :colon: style
4. When data is viewed by users on iPhone, Lion Mac or Android phone, emoji appear normally
5. When data is viewed on PC, older Mac or Linux, emoji are replaced with inline <span> elements with background images or simple images.

While the JS library can replace unified emoji codes (as used by iOS6), it's much slower than replacing colon sequences. By translating to and storing colon sequences on the backend, you are able to:

• Support Android phones (Google emoji codepoints)
• Support older iPhones (Softbank emoji codepoints)
• Allow PC users to enter :smile: and have it appear as an emoji everywhere

Using MySQL for storage

Some special care may be needed to store emoji in your database. While some characters (e.g. Cloud, U+2601) are within the Basic Multilingual Plane (BMP), others (e.g. Close Umbrella, U+1F302) are not. As such, they require 4 bytes of storage to encode each character. Inside MySQL, this requires switching from utf8 storage to utf8mb4.

You can modify a database and table using a statement like:

ALTER DATABASE my_database DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;
ALTER TABLE my_table CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;

You will also need to modify your connection character set.

You don't need to worry about this if you translate to colon syntax before storage.