javascript 如何在javascript中将当前日期时间与另一个日期时间进行比较

How do I compare the current datetime to another datetime in javascript

提问by Eddie

I am looking for some help, trying to compare 2 dates in JavaScript, but haven't managed to find the exact answer on this site yet.

我正在寻找一些帮助，试图在 JavaScript 中比较 2 个日期，但还没有设法在此站点上找到确切的答案。

I am only just starting out with JavaScript and I get the impression that getting the current date\time is not a simple 1 line of code which I thought it would be. I thought I could use a ternary operator but maybe not. I hope I'm wrong but here is my dilemma.

我刚刚开始使用 JavaScript，我的印象是获取当前日期\时间不是我认为的简单的 1 行代码。我以为我可以使用三元运算符，但也许不能。我希望我错了，但这是我的困境。

I want to compare 2 dates. If date1 is before date2 then do something. If not then do something else.

我想比较 2 个日期。如果 date1 在 date2 之前，那么做一些事情。如果没有，那么做别的事情。

• date1: is the current date time. i.e. my system clock
• date2: is a predefined value. I already have this value in the web page: ${expiredDateTime.format("ddMyyyyhm") I believe date 2 is a string but I'm no expert on jquery.

• date1: 是当前日期时间。即我的系统时钟
• date2: 是一个预定义的值。我在网页中已经有了这个值： ${expiredDateTime.format("ddMyyyyhm") 我相信日期 2 是一个字符串，但我不是 jquery 的专家。

Any help with this would be great.

对此的任何帮助都会很棒。

回答by Sankar V

Please try the below code:

请尝试以下代码：

var user="12/11/2012/5/30";
var arrdt= user.split("/");
var userdt = new Date(arrdt[2], arrdt[1] - 1, arrdt[0],arrdt[3],arrdt[4]);
var currdt = new Date();
if (userdt < currdt) {
alert("userdate is before current date");
}else{
alert("userdate is after current date");
}

回答by Sankalp Mishra

The easiest way to compare dates in javascript is to first convert it to a Date object and then compare these date-objects.

在 javascript 中比较日期的最简单方法是首先将其转换为 Date 对象，然后比较这些日期对象。

Below you find an object with three functions:

下面是一个具有三个功能的对象：

dates.compare(a,b)

日期.比较（a，b）

Returns a number:

返回一个数字：

-1 if a < b 0 if a = b 1 if a > b NaN if a or b is an illegal date dates.inRange (d,start,end)

-1 if a < b 0 if a = b 1 if a > b NaN 如果 a 或 b 是非法日期 dates.inRange (d,start,end)

Returns a boolean or NaN:

返回布尔值或 NaN：

true if d is between the start and end (inclusive) false if d is before start or after end. NaN if one or more of the dates are illegal. dates.convert

如果 d 在开始和结束之间（包括），则为 true 如果 d 在开始之前或结束之后，则为 false。如果一个或多个日期是非法的，则为 NaN。日期.convert

Used by the other functions to convert their input to a date object. The input can be

由其他函数使用以将其输入转换为日期对象。输入可以是

a date-object : The input is returned as is. an array: Interpreted as [year,month,day]. NOTE month is 0-11. a number : Interpreted as number of milliseconds since 1 Jan 1970 (a timestamp) a string : Several different formats is supported, like "YYYY/MM/DD", "MM/DD/YYYY", "Jan 31 2009" etc. an object: Interpreted as an object with year, month and date attributes. NOTE month is 0-11.

日期对象：输入按原样返回。数组：解释为 [年、月、日]。注意月份是 0-11。数字：解释为自 1970 年 1 月 1 日以来的毫秒数（时间戳） 字符串：支持几种不同的格式，如“YYYY/MM/DD”、“MM/DD/YYYY”、“2009 年 1 月 31 日”等。 object：解释为具有年、月和日期属性的对象。注意月份是 0-11。

 // Source: http://stackoverflow.com/questions/497790
    var dates = {
        convert:function(d) {
            // Converts the date in d to a date-object. The input can be:
            //   a date object: returned without modification
            //  an array      : Interpreted as [year,month,day]. NOTE: month is 0-11.
            //   a number     : Interpreted as number of milliseconds
            //                  since 1 Jan 1970 (a timestamp) 
            //   a string     : Any format supported by the javascript engine, like
            //                  "YYYY/MM/DD", "MM/DD/YYYY", "Jan 31 2009" etc.
            //  an object     : Interpreted as an object with year, month and date
            //                  attributes.  **NOTE** month is 0-11.
            return (
                d.constructor === Date ? d :
                d.constructor === Array ? new Date(d[0],d[1],d[2]) :
                d.constructor === Number ? new Date(d) :
                d.constructor === String ? new Date(d) :
                typeof d === "object" ? new Date(d.year,d.month,d.date) :
                NaN
            );
        },
        compare:function(a,b) {
            // Compare two dates (could be of any type supported by the convert
            // function above) and returns:
            //  -1 : if a < b
            //   0 : if a = b
            //   1 : if a > b
            // NaN : if a or b is an illegal date
            // NOTE: The code inside isFinite does an assignment (=).
            return (
                isFinite(a=this.convert(a).valueOf()) &&
                isFinite(b=this.convert(b).valueOf()) ?
                (a>b)-(a<b) :
                NaN
            );
        },
        inRange:function(d,start,end) {
            // Checks if date in d is between dates in start and end.
            // Returns a boolean or NaN:
            //    true  : if d is between start and end (inclusive)
            //    false : if d is before start or after end
            //    NaN   : if one or more of the dates is illegal.
            // NOTE: The code inside isFinite does an assignment (=).
           return (
                isFinite(d=this.convert(d).valueOf()) &&
                isFinite(start=this.convert(start).valueOf()) &&
                isFinite(end=this.convert(end).valueOf()) ?
                start <= d && d <= end :
                NaN
            );
        }
    }

回答by Orel Eraki

Possible douplicate for link

链接可能重复

if (date1.getTime() > date2.getTime()) {
    alert("The first date is after the second date!");
}

Reference to Date object

引用日期对象

回答by Ripa Saha

try below code for getting current month, year , date

尝试使用以下代码获取当前月份、年份、日期

var date = new Date();
var currentMonth = date.getMonth();
var currentDate = date.getDate();
var currentYear = date.getFullYear();