Javascript 给定月份的 JS 开始和结束时刻

Moment JS start and end of given month

提问by Fabio B.

I need to calculate a JS date given year=2014 and month=9 (September 2014).

我需要计算给定 year=2014 和 month=9（2014 年 9 月）的 JS 日期。

I tried this:

我试过这个：

var moment = require('moment');
var startDate = moment( year+'-'+month+'-'+01 + ' 00:00:00' );
            var endDate = startDate.endOf('month');
            console.log(startDate.toDate());
            console.log(endDate.toDate());

Both of logs show:

两个日志都显示：

Tue Sep 30 2014 23:59:59 GMT+0200 (CEST)
Tue Sep 30 2014 23:59:59 GMT+0200 (CEST)

End date is correct but... why the start date is not?

结束日期是正确的，但是...为什么开始日期不是？

回答by klyd

That's because endOfmutates the original value.

那是因为endOf改变了原始值。

Relevant quote:

相关报价：

Mutates the original moment by setting it to the end of a unit of time.

通过将原始时刻设置为单位时间的结尾来改变原始时刻。

Here's an example function that gives you the output you want:

这是一个示例函数，可为您提供所需的输出：

function getMonthDateRange(year, month) {
    var moment = require('moment');

    // month in moment is 0 based, so 9 is actually october, subtract 1 to compensate
    // array is 'year', 'month', 'day', etc
    var startDate = moment([year, month - 1]);

    // Clone the value before .endOf()
    var endDate = moment(startDate).endOf('month');

    // just for demonstration:
    console.log(startDate.toDate());
    console.log(endDate.toDate());

    // make sure to call toDate() for plain JavaScript date type
    return { start: startDate, end: endDate };
}

References:

参考：

• endOf()
• clone()
• Date from object

• endOf()
• clone()
• Date from object

回答by Shakti Jadon

you can use this directly for the end or start date of the month

您可以直接将其用于本月的结束或开始日期

new moment().startOf('month').format("YYYY-DD-MM");
new moment().endOf("month").format("YYYY-DD-MM");

you can change the format by defining a new format

您可以通过定义新格式来更改格式

回答by bakkal

When you use .endOf()you are mutating the object it's called on, so startDatebecomes Sep 30

当您使用时，.endOf()您正在改变它所调用的对象，因此startDate变为 Sep 30

You should use .clone()to make a copy of it instead of changing it

您应该使用.clone()复制它而不是更改它

var startDate = moment(year + '-' + month + '-' + 01 + ' 00:00:00');
            var endDate = startDate.clone().endOf('month');
            console.log(startDate.toDate());
            console.log(endDate.toDate());

Mon Sep 01 2014 00:00:00 GMT+0700 (ICT) 
Tue Sep 30 2014 23:59:59 GMT+0700 (ICT) 

回答by Sanjay Singh

Try the following code:

试试下面的代码：

const moment=require('moment');
console.log("startDate=>",moment().startOf('month').format("YYYY-DD-MM"));
console.log("endDate=>",moment().endOf('month').format("YYYY-DD-MM"));

回答by Sandeep Gantait

Don't really think there is some direct method to get the last day but you could do something like this:

不要真的认为有一些直接的方法可以得到最后一天，但你可以这样做：

var dateInst = new moment();
/**
 * adding 1 month from the present month and then subtracting 1 day, 
 * So you would get the last day of this month 
 */
dateInst.add(1, 'months').date(1).subtract(1, 'days');
/* printing the last day of this month's date */
console.log(dateInst.format('YYYY MM DD'));

回答by nikhil

your startDate is first-day-of-month, In this case we can use

您的 startDate 是第一天的月份，在这种情况下，我们可以使用

var endDate = moment(startDate).add(1, 'months').subtract(1, 'days');

Hope this helps!!

希望这可以帮助！！

回答by IfThenElse

var d = new moment();
var startMonth = d.clone().startOf('month');
var endMonth = d.clone().endOf('month');
console.log(startMonth, endMonth);

doc

文档

回答by JSON C11

const year = 2014;
const month = 09;

// months start at index 0 in momentjs, so we subtract 1
const startDate = moment([year, month - 1, 01]).format("YYYY-MM-DD");

// get the number of days for this month
const daysInMonth = moment(startDate).daysInMonth();

// we are adding the days in this month to the start date (minus the first day)
const endDate = moment(startDate).add(daysInMonth - 1, 'days').format("YYYY-MM-DD");

console.log(`start date: ${startDate}`);
console.log(`end date:   ${endDate}`);

<script
src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.20.1/moment.min.js">
</script>

回答by bharat patel

const dates = getDatesFromDateRange("2014-05-02", "2018-05-12", "YYYY/MM/DD", 1);           
console.log(dates);
// you get the whole from-to date ranges as per parameters
var onlyStartDates = dates.map(dateObj => dateObj["to"]);
console.log(onlyStartDates);
// moreover, if you want only from dates then you can grab by "map" function

function getDatesFromDateRange( startDate, endDate, format, counter ) {
    startDate = moment(startDate, format);
    endDate = moment(endDate, format);

    let dates = [];
    let fromDate = startDate.clone();
    let toDate = fromDate.clone().add(counter, "month").startOf("month").add(-1, "day");
    do {
        dates.push({
            "from": fromDate.format(format),
            "to": ( toDate < endDate ) ? toDate.format(format) : endDate.format(format)
        });
        fromDate = moment(toDate, format).add(1, "day").clone();
        toDate = fromDate.clone().add(counter, "month").startOf("month").add(-1, "day");
    } while ( fromDate < endDate );
    return dates;
}

Please note, .clone() is essential in momentjs else it'll override the value. It seems in your case.

请注意， .clone() 在 momentjs 中是必不可少的，否则它会覆盖该值。看来你的情况。

It's more generic, to get bunch of dates that fall between dates.

它更通用，以获得落在日期之间的一堆日期。

回答by enrique ramos

The following code should work:

以下代码应该可以工作：

$('#reportrange').daterangepicker({
                startDate: start,
                endDate: end,
                ranges: {
                    'Hoy': [moment(), moment()],
                    'Ayer': [moment().subtract(1, 'days'), moment().subtract(1, 'days')],
                    'Ultimos 7 dias': [moment().subtract(6, 'days'), moment()],
                    'Ultimos 30 dias': [moment().subtract(29, 'days'), moment()],
                    'Mes actual': [moment().startOf('month'), moment().endOf('month')],
                    'Ultimo mes': [moment().subtract(1, 'month').startOf('month'), moment().subtract(1, 'month').endOf('month')],
                    'Enero': [moment().month(0).startOf('month') , moment().month(0).endOf('month')],
                    'Febrero': [moment().month(1).startOf('month') , moment().month(1).endOf('month')],
                    'Marzo': [moment().month(2).startOf('month') , moment().month(2).endOf('month')],
                    'Abril': [moment().month(3).startOf('month') , moment().month(3).endOf('month')],
                    'Mayo': [moment().month(4).startOf('month') , moment().month(4).endOf('month')],
                    'Junio': [moment().month(5).startOf('month') , moment().month(5).endOf('month')],
                    'Julio': [moment().month(6).startOf('month') , moment().month(6).endOf('month')],
                    'Agosto': [moment().month(7).startOf('month') , moment().month(7).endOf('month')],
                    'Septiembre': [moment().month(8).startOf('month') , moment().month(8).endOf('month')],
                    'Octubre': [moment().month(9).startOf('month') , moment().month(9).endOf('month')],
                    'Noviembre': [moment().month(10).startOf('month') , moment().month(10).endOf('month')],
                    'Diciembre': [moment().month(11).startOf('month') , moment().month(11).endOf('month')]
                }
            }, cb);