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How to detect Emojis With JavaScript
Use regular expression to match Emojis in Strings
I recently filtered a vast Twitter timeline to analyze it using a deep neural network. As you know, tweets can contain different kinds of content, including emojis. So one of the first steps was to clean the data, in this case removing all emoticons from the timeline.
Although this can be done in many ways, I will show how to do it with JavaScript because it is straightforward and fast, so let’s start.
As you might be guessing from the subtitle of this post, we will use regular expressions to do it.
Modern browsers support Unicode property, which allows you to match emojis based on their belonging in the Emoji Unicode category. For example, you can use Unicode property escapes like \p{Emoji} or \P{Emoji} to match/no match emoji characters. Note that 0123456789#* and other characters are interpreted as emojis using the previous Unicode category. Therefore, a better way to do this is to use the {Extended_Pictographic} Unicode category that denotes all the characters typically understood as emojis instead of the {Emoji} category.
Let’s see some examples.
Use \p{} to match the Unicode characters
If you use the “Emoji” Unicode category, you may get incorrect results:
const withEmojis = /\p{Emoji}/u
withEmojis.test('😀');
//truewithEmojis.test('ab');
//falsewithEmojis.test('1');
//true opps!
Therefore it is better to use the Extended_Pictographic scape as previously mentioned:
const withEmojis = /\p{Extended_Pictographic}/u
withEmojis.test('😀😀');
//truewithEmojis.test('ab');
//falsewithEmojis.test('1');
//false
Use \P{} to negate the match.
const noEmojis = /\P{Extended_Pictographic}/u
noEmojis.test('😀');
//falsenoEmojis.test('1212');
//false
As you can see, this is an easy way to detect Emojis, but if you use our previous withEmojis regex with a grouped emoji, you will be surprised by the result.
