使用Moment.js每月生成几天失败

Question

const generateDatesOfAMonth = () => {

    let start_date_of_month = moment().format("YYYY-MM-01"),
    end_date_of_month = moment().format("YYYY-MM-") + moment().daysInMonth(),
    dayArray = [];

    while (start_date_of_month <= end_date_of_month) {
        dayArray.push({ days: start_date_of_month });
        start_date_of_month = moment(start_date_of_month).add(1, 'days');
    }
    return dayArray;
}

What's wrong with my code above? We can know number of days of each month, I found a solution via moment, but is my loop wrong? I expect an array of days but what I got is only 1st day. Hmm, any clue?

Answer 1

I think start_date_of_month = moment(start_date_of_month).add(1, 'days');

should be start_date_of_month = start_date_of_month.add(1, 'days');

Check out this resource: Format date and Subtract days using Moment.js

Answer 2

@AlenJenshen: Sorry, I do not have enough reputation to comment your question. But there are the solution for your question:

const generateDatesOfAMonth = () => {

    let start_date_of_month = moment().format("YYYY-MM-01"),
    end_date_of_month = moment().format("YYYY-MM-") + moment().daysInMonth(),
    dayArray = [];


    while (start_date_of_month <= end_date_of_month) {
        dayArray.push({ days: start_date_of_month });
        start_date_of_month = moment(start_date_of_month).add(1, 'days').format("YYYY-MM-DD");
    }
    return dayArray;
}

You forgot to format start_date_of_month , so while loop can not compare start_date to end_date. Please try my solution :)

Answer 3

You can use [...Array(moment().daysInMonth()).keys()]; to build and array with an element for each day of the month (eg [1, ... 31] ). Then you can use date() and format() to get your result.

Here a live working sample:

 const generateDatesOfAMonth = () => { // Get array of numbers for each day of the month let days = [...Array(moment().daysInMonth()).keys()]; // Create a moment object for each day and format it let dayArray = days.map( day => { return { days: moment().date(day+1).format('YYYY-MM-DD') } }); return dayArray; } console.log( generateDatesOfAMonth() ); 

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