jQuery addClass example

Change class name on click in jQuery

by Fu-Ching Hsiao

CSS

body {
  background: #20262E;
  padding: 20px;
  font-family: Helvetica;
}

#banner-message {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  font-size: 25px;
  text-align: center;
  transition: all 0.2s;
  margin: 0 auto;
  width: 300px;
}

button {
  background: #0084ff;
  border: none;
  border-radius: 5px;
  padding: 8px 14px;
  font-size: 15px;
  color: #fff;
}

#banner-message.alt {
  background: #0084ff;
  color: #fff;
  margin-top: 40px;
  width: 200px;
}

#banner-message.alt button {
  background: #fff;
  color: #000;
}

JavaScript

"use strict";
class temp {
    constructor(a, b, c ='aaa') {
        this.a = a;
        this.b = b;
		this.c = c;
    }
	p(){
		if('undefined' === typeof this.c){
		console.log("xxx");
		}
		console.log(this.a);
		console.log(this.c);
	}
}
let t = new temp(1,2);
t.p();

new temp(2,3).p();