注:ie10+
var str = window.btoa("liusong");
console.log(str);
var s = window.atob("bGl1c29uZw==")
console.log(s);
//应对中文解析
var ss = window.btoa(window.encodeURI("刘松"));
console.log(ss);
var ss1 = window.decodeURI(window.atob("JUU1JTg4JTk4JUU2JTlEJUJF"));
console.log(ss1);