How to access a DOM element in React? What is the equilvalent of document.getElementById() in React

Question

How do I select certain bars in react.js?

This is my code:

var Progressbar = React.createClass({
    getInitialState: function () {
        return {          


        

Answer 1

You can replace

document.getElementById(this.state.baction).addPrecent(10);

with

this.refs[this.state.baction].addPrecent(10);