例如，在输入框中给定两个日期:
<input id="first" value="1/1/2000"/>
<input id="second" value="1/1/2001"/>
<script>
alert(datediff("day", first, second)); // what goes here?
</script>
如何在JavaScript中获得两个日期之间的天数?
当前回答
区分两个日期的最简单方法是:
var diff = Math.floor((Date.parse(str2) - Date.parse(str1)) / 86400000);
您将得到不同的天数(如果其中一个或两个都无法解析，则为NaN)。解析日期给出了以毫秒为单位的结果，要按天得到它，你必须除以24 * 60 * 60 * 1000
如果你想用天、小时、分钟、秒和毫秒来划分:
function dateDiff( str1, str2 ) {
var diff = Date.parse( str2 ) - Date.parse( str1 );
return isNaN( diff ) ? NaN : {
diff : diff,
ms : Math.floor( diff % 1000 ),
s : Math.floor( diff / 1000 % 60 ),
m : Math.floor( diff / 60000 % 60 ),
h : Math.floor( diff / 3600000 % 24 ),
d : Math.floor( diff / 86400000 )
};
}
以下是我对James版本的重构版本:
function mydiff(date1,date2,interval) {
var second=1000, minute=second*60, hour=minute*60, day=hour*24, week=day*7;
date1 = new Date(date1);
date2 = new Date(date2);
var timediff = date2 - date1;
if (isNaN(timediff)) return NaN;
switch (interval) {
case "years": return date2.getFullYear() - date1.getFullYear();
case "months": return (
( date2.getFullYear() * 12 + date2.getMonth() )
-
( date1.getFullYear() * 12 + date1.getMonth() )
);
case "weeks" : return Math.floor(timediff / week);
case "days" : return Math.floor(timediff / day);
case "hours" : return Math.floor(timediff / hour);
case "minutes": return Math.floor(timediff / minute);
case "seconds": return Math.floor(timediff / second);
default: return undefined;
}
}
其他回答
如果你有两个unix时间戳，你可以使用这个函数(为了清晰起见，写得更详细一点):
// Calculate number of days between two unix timestamps
// ------------------------------------------------------------
var daysBetween = function(timeStampA, timeStampB) {
var oneDay = 24 * 60 * 60 * 1000; // hours * minutes * seconds * milliseconds
var firstDate = new Date(timeStampA * 1000);
var secondDate = new Date(timeStampB * 1000);
var diffDays = Math.round(Math.abs((firstDate.getTime() - secondDate.getTime())/(oneDay)));
return diffDays;
};
例子:
daysBetween(1096580303, 1308713220); // 2455
我最近也有同样的问题，因为我来自Java世界，所以我立即开始搜索JavaScript的JSR 310实现。JSR 310是Java的日期和时间API (Java 8的标准版本)。我认为这个API设计得很好。
幸运的是，有一个直接的Javascript端口，称为js-joda。
首先，在<head>中包含js-joda:
<script
src="https://cdnjs.cloudflare.com/ajax/libs/js-joda/1.11.0/js-joda.min.js"
integrity="sha512-piLlO+P2f15QHjUv0DEXBd4HvkL03Orhi30Ur5n1E4Gk2LE4BxiBAP/AD+dxhxpW66DiMY2wZqQWHAuS53RFDg=="
crossorigin="anonymous"></script>
然后简单地这样做:
let date1 = JSJoda.LocalDate.of(2020, 12, 1);
let date2 = JSJoda.LocalDate.of(2021, 1, 1);
let daysBetween = JSJoda.ChronoUnit.DAYS.between(date1, date2);
现在daysBetween包含了间隔的天数。注意，结束日期是独占的。
夏令时问题使这里的许多答案无效。我将使用一个helper函数来获得给定日期的唯一天数——通过使用UTC方法:
const dayNumber = a => Date.UTC(a.getFullYear(), a.getMonth(), a.getDate()) / (24*60*60*1000); const daysBetween = (a, b) => dayNumber(b) - dayNumber(a); // Testing it const start = new Date(1000, 0, 1); // 1 January 1000 const end = new Date(3000, 0, 1); // 1 January 3000 let current = new Date(start); for (let days = 0; current < end; days++) { const diff = daysBetween(start, current); if (diff !== days) throw "test failed"; current.setDate(current.getDate() + 1); // move current date one day forward } console.log("tests succeeded");
更好的解决方案
忽略时间部分
如果两个日期相同，则返回0。
function dayDiff(firstDate, secondDate) { firstDate = new Date(firstDate); secondDate = new Date(secondDate); if (!isNaN(firstDate) && !isNaN(secondDate)) { firstDate.setHours(0, 0, 0, 0); //ignore time part secondDate.setHours(0, 0, 0, 0); //ignore time part var dayDiff = secondDate - firstDate; dayDiff = dayDiff / 86400000; // divide by milisec in one day console.log(dayDiff); } else { console.log("Enter valid date."); } } $(document).ready(function() { $('input[type=datetime]').datepicker({ dateFormat: "mm/dd/yy", changeMonth: true, changeYear: true }); $("#button").click(function() { dayDiff($('#first').val(), $('#second').val()); }); }); <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <link rel="stylesheet" href="//code.jquery.com/ui/1.12.1/themes/base/jquery-ui.css"> <script src="//code.jquery.com/ui/1.12.1/jquery-ui.js"></script> <input type="datetime" id="first" value="12/28/2016" /> <input type="datetime" id="second" value="12/28/2017" /> <input type="button" id="button" value="Calculate">
我来找这个小工具在里面你会找到这个的函数。这里有一个简短的例子:
<script type="text/javascript" src="date.js"></script>
<script type="text/javascript">
var minutes = 1000*60;
var hours = minutes*60;
var days = hours*24;
var foo_date1 = getDateFromFormat("02/10/2009", "M/d/y");
var foo_date2 = getDateFromFormat("02/12/2009", "M/d/y");
var diff_date = Math.round((foo_date2 - foo_date1)/days);
alert("Diff date is: " + diff_date );
</script>
