一、获取年月日时分秒

function getCurrentDate() {
	let now = new Date();
	let year = now.getFullYear(); // 获取年份
	let month = now.getMonth(); // 获取月份
	let date = now.getDate(); // 获取日期
	let day = now.getDay(); // 获取周几
	let hour = now.getHours(); // 获取小时
	let minu = now.getMinutes(); // 获取分钟
	let sec = now.getSeconds(); // 获取秒
	let MS = now.getMilliseconds(); //获取毫秒
	let week;
	month = month + 1;
	if (month < 10) month = "0" + month;
	if (date < 10) date = "0" + date;
	if (hour < 10) hour = "0" + hour;
	if (minu < 10) minu = "0" + minu;
	if (sec < 10) sec = "0" + sec;
	if (MS < 100)MS = "0" + MS;
	let arr_week = new Array("星期日", "星期一", "星期二", "星期三", "星期四", "星期五", "星期六");
	week = arr_week[day];
	let time = "";
	time = year + "年" + month + "月" + date + "日" + " " + hour + ":" + minu + ":" + sec + " " + week;
	// 获取当前日期的函数的执行间隔时间，每1000毫秒刷新一次。
	let timer = setTimeout(() => { this.getCurrentDate() }, 1000);
	console.log(time,'===>time');
	console.log(timer,'===>timer');
}

二、获取当前日期

function time() {
    let day = new Date();
	day.setTime(day.getTime());
	var today = day.getFullYear()+"-" + (day.getMonth()+1) + "-" + day.getDate();
}

三、获取昨天的日期

function time() {
     var day = new Date();
     day.setTime(day.getTime()-24*60*60*1000);
     var yesterday = day.getFullYear()+"-" + (day.getMonth()+1) + "-" + day.getDate();
 }

四、获取明天的日期

function time() {
     var day = new Date();
     day.setTime(day.getTime()+24*60*60*1000);
     var tomorrow = day.getFullYear()+"-" + (day.getMonth()+1) + "-" + day.getDate();
 }

五、获取当天日期的0点

function getStartTime(time) {
  return new Date(new Date(time).toLocaleDateString()).getTime()/1000
}

六、获取当天日期的23:59点

function getEndTime(time) {
  return (new Date(new Date(time).toLocaleDateString()).getTime() +24 * 60 * 60 * 1000 -1)/1000
}

new Date( +new Date() + 8 * 3600 * 1000 ).toJSON().substr(0,19).replace("T"," ")

--获取datetime的年
select DATEPART(year,GETDATE())
--获取datetime的月
select DATEPART(MONTH ,GETDATE())
--获取datetime的日
select DATEPART(day ,GETDATE())
--获取datetime的时
select DATEPART(hour ,GETDATE())
--获取datetime的分
select DATEPART(MINUTE ,GETDATE())
--获取datetime的秒
select DATEPART(SECOND ,GETDATE())