js-emoji - Display emoji in the browser, everywhere

Modern computers and phones allow the display and input of emoji, but you often want to display them on older devices, or in the browser. 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.

Installation

Either clone the git repo, or npm install emoji-js

Browser Usage

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

var emoji = new EmojiConvertor();

// 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);

// convert colons explicitly to unicode
emoji.replace_mode = 'unified';
emoji.allow_native = true;
var output3 = emoji.replace_colons(input);

</script>

You can view a live demo here.

Node Usage

After installing the package via npm install emoji-js:

var EmojiConvertor = require('emoji-js');

var emoji = new EmojiConvertor();

console.log(emoji.replace_colons("Hello :smile:"));

Output control

There are many options to control the format of the replacement, although the defaults should work well on all platforms. There are two overrides which ignore all other replacement-mode preferences:

emoji.text_mode = true - force text output mode, e.g. smile (default false)
emoji.colons_mode = true - force colon output mode, e.g. :smile: (default: false)

After that, the mode is determined automatically by examining the environment and determining capabilities. You can introspect the auto-detected mode by checking emoji.replace_mode, which can have the following values:

unified - Output Unicode code points
softbank - Output legacy Softbank/iOS code points
google - Output legacy Android code points
css - Output HTML images, using  elements with CSS background images
img - Output HTML images, using <img> elements

You can explicitly override the emoji.replace_mode to any of the above values. There are a few options which determine how the emoji.replace_mode value is used at run-time:

emoji.allow_native = true - Allow output of code points (default: true, otherwise falls back to css or img mode)
emoji.use_sheet = true - Use spritesheets with CSS positioning, instead of individual images (default: false, only applies in css mode)
emoji.use_css_imgs = true - Use individual CSS classes for each emoji, rather than inlining the positioning (default: false, only applies in css mode, requires the CSS file to be loaded)
emoji.avoid_ms_emoji = true - For browsers on Windows, don't allow native code points (because they look awful) (default: true)

There are also some further options that change the nature of the output under various modes:

emoji.wrap_native = true - Wrap native code points in  to allow styling (default: false, only applies in native, google and softbank modes)
emoji.include_title = true - Set the "title" property on the  or <img> tag to the short-name, e.g. :smile: (default: false, only applies in css and img modes)
emoji.include_text = true - Set the text inside the  tag to the short-name, e.g. :smile: (default: false, only applies in css mode)

Images

The library supports using multiple image sets, which can be selected using the emoji.img_set property. Valid values are:

apple (default)
google
twitter
facebook
messenger

This value is used as a lookup in the emoji.img_sets property, which defines each set. By default, it assumes your images are under the path /emoji-data/, but you can override these values:

emoji.img_sets.apple.path = 'http://my-cdn.com/emoji-apple-64/';
emoji.img_sets.apple.sheet = 'http://my-cdn.com/emoji-apple-sheet-64.png';

The .path property, the directory containing individual images, must end in a trailing slash. The .sheet property points directly to a spritesheet. The images can be found in the emoji-data repository: https://github.com/iamcal/emoji-data

Make sure you use the same version of the images that this library was built with, otherwise spritesheets will not work, and some images may be wrong or missing!

If you need to cache-bust your images, you can use the following property:

emoji.img_suffix = '?foo';

This will cause the generated URLs to have ?foo appended (default: '').

Further options

If you wish to allow :SMILE: to work the same as :smile:, you can set emoji.allow_caps = true (default: false)

You can add your own emoji aliases, even overriding built-in emoji:

emoji.addAliases({
  'doge' : '1f415',
  'cat'  : '1f346'
});

You can then remove your custom aliases, which will also reset built-in emoji back to their original state:

emoji.removeAliases([
  'doge',
  'cat',
]);

Upgrading from 1.x or 2.x

Prior to version 3.0, the emoji.js library would instantiate a global object called emoji, which you would call methods on. In versions 3.0 and later, the library exposes a single class called EmojiConvertor which needs to be instantiated manually. To upgrade old code, simply add this line in a global context:

var emoji = new EmojiConvertor();

Lifecycle

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

User enters text on a modern device, containing native emoji
Data is stored by application, optionally translated to :colon: style
When data is viewed by users on iPhone, Mac or Android phone, emoji appear natively
When data is viewed on older devices, emoji are replaced with inline  elements with background images or simple images.

While the JS library can replace native emoji codepoints, it's significantly slower than replacing colon sequences. By translating to and storing colon sequences on the backend, you are able to:

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

Using MySQL for storage

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

Version History

See CHANGES.md

frontapp/js-emoji