新增 cookie
var day = new Date();
day.setTime(day.getTime() + 72 * 60 * 60 * 1000); //设置 cookie 3天后到期
document.cookie = 'name=小明;' + " expires=" + day.toGMTString();//设置
document.cookie = 'age=小亮;' + " expires=" + day.toGMTString();//设置
获取 cookie
let cookie= document.cookie；
//name=小明; age=18
删除cookie
let exp = new Date();
exp.setDate(exp.getDate() - 1);//直接设置 cookie 的过期时间
document.cookie = "name=小明" + ";expires=" + exp;
