How to use Javascript to get the date n days ago_javascript tips

复制代码 代码如下:

 function Test(day) {
                var today = new Date();
                var beforMilliseconds = today.getTime() - 1000 * 3600 * 24 * day;
                var beforday = new Date();
                beforday.setTime(beforMilliseconds);
                var strYear = beforday.getFullYear();
                var strDay = beforday.getDate();
                var strMonth = beforday.getMonth() 1;
                if (strMonth < 10) {
                    strMonth = "0" strMonth;
                }
                var strYesterday = strYear "-" strMonth "-" strDay;
                alert(strYesterday);
            }