1.JS求时间差

注意：如果时间自己自己传入参数，要进行转换。比如date2 = new Date(Date.parse(time1))

var date1=new Date();  //开始时间
alert("aa");
var date2=new Date();    //结束时间
var date3=date2.getTime()-date1.getTime()  //时间差的毫秒数
 

//计算出相差天数
var days=Math.floor(date3/(24*3600*1000))
 
//计算出小时数

var leave1=date3%(24*3600*1000)    //计算天数后剩余的毫秒数
var hours=Math.floor(leave1/(3600*1000))
//计算相差分钟数
var leave2=leave1%(3600*1000)        //计算小时数后剩余的毫秒数
var minutes=Math.floor(leave2/(60*1000))
 

//计算相差秒数
var leave3=leave2%(60*1000)      //计算分钟数后剩余的毫秒数
var seconds=Math.round(leave3/1000)
 

alert(" 相差 "+days+"天 "+hours+"小时 "+minutes+" 分钟"+seconds+" 秒")

2.显示本站已运行x天x时x分x秒，

稍稍麻烦的就是，要计算两个时间之间的年数差，必须要考虑平年和闰年的问题。
拓展：怎样才是闰年？
需要同时满足两个条件：
1、年份能被4整除；
2、年份若是100的整数倍的话,需被400整除,否则是平年
比如：1900年能被4整除,但是因为其是100的整数倍,却不能被400整除,所以是平年

//初始化时间
//为了提高兼容性注意创建日期的格式，还要添加引号
var start = new Date("2000/12/1");
//把以下内容放到script标签内，创建id为times的div，并开启下面一条语句注释
//show_date_time();

function show_date_time(){
	//周期性调用show_date_time()方法
	setTimeout("show_date_time()", 1000);

	var current = new Date();
	//总秒数
	var millisecond = Math.floor((current.getTime() - start.getTime())/1000);
	
	//总天数
	var allDay = Math.floor(millisecond/(24*60*60));

	//注意同getYear的区别
	var startYear = start.getFullYear();
	var currentYear = current.getFullYear();
	
	//闰年个数
	var leapYear = 0;
	for(var i=startYear;i<currentYear;i++){
		if(isLeapYear(i)){
			leapYear++;
		}
	}

	//年数
	var year = Math.floor((allDay - leapYear*366)/365 + leapYear);;
	//天数
        var day;
        if(allDay > 366){
	        day = (allDay - leapYear*366)%365;
        }else{
                day = allDay;
        }
	//取余数(秒)
	var remainder = millisecond%(24*60*60);
	//小时数
	var hour = Math.floor(remainder/(60*60));
	//分钟数
	var minute = Math.floor(remainder%(60*60)/60);
	//秒数
	var second = remainder - hour*60*60 - minute*60; 
	var span = "本站已运行" + (year>0 ? (year + "年"):"") + day + "天" 
        + hour + "小时" + minute + "分" + second + "秒" ; 
	document.getElementById("times").innerHTML = span;
}

//判断是否是闰年
function isLeapYear(year){
	if((year%4==0 && year%100!=0)||(year%100==0 && year%400==0)){
		return true;
	}
	return false;
}

 function GetRequest() {//截取浏览器地址栏传的参数
        var url = decodeURI(location.search); //获取url中"?"符后的字串
        var theRequest = new Object();
        if (url.indexOf("?") != -1) {
            var str = url.substr(1);
            strs = str.split("&");
            for (var i = 0; i < strs.length; i++) {
                theRequest[strs[i].split("=")[0]] = unescape(strs[i].split("=")[1]);
            }
        }
        return theRequest;
    }
 var Request = GetRequest();
        var relateSelect = Request["relateSelect"];
        $('#relateSelect').val(relateSelect);     

获取当前时间 包括年月日 时分秒。。。可以用在初始化时间控件为默认当天时间范围。

function getNowFormatDate() {
    var day = new Date();
    var Year = 0;
    var Month = 0;
    var Day = 0;
    var Hour = 0;
    var Minute = 0;
    var Second = 0;
    var CurrentDate = "";
    //初始化时间
    Year = day.getFullYear();
    Month = day.getMonth() + 1;
    Day = day.getDate();
    Hour = day.getHours();
    Minute = day.getMinutes();
    Second = day.getSeconds();
    CurrentDate = CurrentDate + Year + "-";
    if (Month >= 10) {
        CurrentDate = CurrentDate + Month + "-";
    }
    else {
        CurrentDate = CurrentDate + "0" + Month + "-";
    }
    if (Day >= 10) {
        CurrentDate = CurrentDate + Day;
    }
    else {
        CurrentDate = CurrentDate + "0" + Day;
    }

    if (Hour >= 10) {
        CurrentDate += " " + Hour;
    }
    else {
        CurrentDate += " 0" + Hour;
    }
    if (Minute >= 10) {
        CurrentDate = CurrentDate + ":" + Minute;
    }
    else {
        CurrentDate = CurrentDate + ":0" + Minute;
    }
    if (Second >= 10) {
        CurrentDate = CurrentDate + ":" + Second;
    }
    else {
        CurrentDate = CurrentDate + ":0" + Second;
    }

    return CurrentDate;
}

获取当天开始时间 包括年月日 时分秒

function getTodayFormatDate() {
    var day = new Date();
    var Year = 0;
    var Month = 0;
    var Day = 0;
    var Hour = 0;
    var Minute = 0;
    var Second = 0;
    var CurrentDate = "";
    //初始化时间
    Year = day.getFullYear();
    Month = day.getMonth() + 1;
    Day = day.getDate();
    Hour = day.getHours();
    Minute = day.getMinutes();
    Second = day.getSeconds();
    CurrentDate = CurrentDate + Year + "-";
    if (Month >= 10) {
        CurrentDate = CurrentDate + Month + "-";
    }
    else {
        CurrentDate = CurrentDate + "0" + Month + "-";
    }
    if (Day >= 10) {
        CurrentDate = CurrentDate + Day;
    }
    else {
        CurrentDate = CurrentDate + "0" + Day;
    }

    CurrentDate += " 00";
    CurrentDate = CurrentDate + ":00";
    CurrentDate = CurrentDate + ":00";

    return CurrentDate;
}

格式化时间格式为2018-06-07 15:33

function formatterDateTime(time) {//时间格式转换
                var date = new Date(time);
                var y = date.getFullYear();
                var m = date.getMonth() + 1;
                m = m < 10 ? ('0' + m) : m;
                var d = date.getDate();
                d = d < 10 ? ('0' + d) : d;
                var h = date.getHours();
                var minute = date.getMinutes();
                minute = minute < 10 ? ('0' + minute) : minute;
                return y + '-' + m + '-' + d + ' ' + h + ':' + minute;
            }