JavaScript 获取 当前日期和三十天以前日期

//获取当前日期
var myDate = new Date();
var nowY = myDate.getFullYear();
var nowM = myDate.getMonth()+1;
var nowD = myDate.getDate();
var enddate = nowY+"-"+(nowM<10 ? "0" + nowM : nowM)+"-"+(nowD<10 ? "0"+ nowD : nowD);//当前日期 //获取三十天前日期
var lw = new Date(myDate - 1000 * 60 * 60 * 24 * 30);//最后一个数字30可改，30天的意思
var lastY = lw.getFullYear();
var lastM = lw.getMonth()+1;
var lastD = lw.getDate();
var startdate=lastY+"-"+(lastM<10 ? "0" + lastM : lastM)+"-"+(lastD<10 ? "0"+ lastD : lastD);//三十天之前日期