How to know that this string is Emoji?

Ionic Framework ionic-v3
1

Еxample:
this.text = '😁'; // this.text.length will be 2

How to know that this is 1 character and it is Emoji?

I will be grateful for any idea.

2

maybe there is some sort of unicode emojii prefix that you can test for.
Test with a list off all emojis ( this list has to be updated with every unicode/android/ios update to contain the new emojis) maybe some json like that https://www.npmjs.com/package/emoji.json