title: Angular 2 Twitter Character Countdown on Input
body: <p>I'm trying to implement a "character countdown" in Angular 2 on an input element, similar to how Twitter enforces the 140 character limit and updates the user in real time. I'd like to show the user how many characters they have left in real-time, so as the user types into the input, the character countdown updates and, ultimately will reach "0" as the user continues to type. </p>
  
  <p>I understand how to enforce the "maxlength" on the input element, but I'm requesting guidance on how to implement the countdown. This is a similar request to the Angular 1 post here: <a href="https://stackoverflow.com/questions/20603107/angularjs-text-area-character-counter">angularjs text area character counter</a></p>
  
  <p>Is jQuery necessary here, or is there an "Angular 2 way" through binding that would work?</p>