moment.js usage notes

Introduction:

moment.js is a function library dedicated to processing time, which can be used in browsers and node.js environments.

Installation: npm i moment --save

use:

import moment from 'moment' 

const moment = require('moment')

The moment introduced here is actually a function that returns a moment instance based on the parameters passed in

The moment instance actually wraps a layer of Date objects

There are a large number of methods that moment instances can use, enough to meet daily business needs.

1. Create a moment instance

    1 Create an instance based on the current date: moment ();

    2 Create an instance based on the date object: moment (new Date ());

    3 Create an instance based on the string: moment ('2018--10--10', 'YYYY--MM--DD'); the first parameter is a time string, and the second parameter is the format of the time

If a string is  a time string that conforms to the ISO 8601 standard, you do not need to pass in the second parameter, such as: moment ('2018-10-10')

For the format of time, please refer to the official website http://momentjs.cn/docs/#/parsing/

The second parameter can also be an array in time format, which is used to handle various situations where the format may exist

moment("29-06-1995", ["MM-DD-YYYY", "DD-MM", "DD-MM-YYYY"]); // uses the last format
moment("05-06-1995", ["MM-DD-YYYY", "DD-MM-YYYY"]);          // uses the first format

     4 Create an instance based on the number of milliseconds: moment (Number)

     5 Create an instance based on timestamp: moment (Number)

     6 Copy a moment: moment (Moment) or var a = moment (); var b = a.clone ()

Two. According to the moment instance to obtain the format data we want

var mom = torque ();

1 Obtain the formatting string mom.format ("YYYY-MM-DD HH: mm: ss") (emphasis here, pay attention to the case of minutes and seconds) for details, refer to http://momentjs.cn/docs/#/ displaying /

2 Get and set milliseconds, seconds, day (month), day (week), week, month, and year reference documents

3 Maximum (small) date

moment.max(Moment[,Moment...]);

moment.min(Moment[,Moment...]);

Three operation moment

The moment object is a mutable object, each operation will return a new moment

1 Addition:

moment().add(7, 'days');

2 Cutting method:

moment().subtract(1,'days')

3 Chain call: moment (). Add (1, 'd'). Subtract (1, M)

4 Set the year, month, day, hour, minute, and second:

moment().year(2018).month(0).date(1).hours(0).minutes(0).seconds(0).milliseconds(0);

Four comparison

moment's time is very semantic

1. Whether before

 

moment().isBefore(Moment|String|Number|Date|Array);
moment().isBefore(Moment|String|Number|Date|Array, String);

 The first parameter is time, which can be a moment instance or other. The second parameter is the precision of comparison (if it is year, only the year is compared, if it is day, the year, month, and day are compared)

moment('2010-10-20').isBefore('2010-10-21'); // true

2. Whether after

moment().isAfter(Moment|String|Number|Date|Array);
moment().isAfter(Moment|String|Number|Date|Array, String);

3. Are they the same

moment().isSame(Moment|String|Number|Date|Array);
moment().isSame(Moment|String|Number|Date|Array, String);

4. Whether between

moment().isBetween(moment-like, moment-like);
moment().isBetween(moment-like, moment-like, String);
// where moment-like is Moment|String|Number|Date|Array

The third parameter is also precision

5. Whether it is a leap year

moment().isLeapYear();

6. Whether it is a moment object

moment.isMoment(obj);

 7 Same or before, same or after

moment().isSameOrBefore(Moment|String|Number|Date|Array);
moment().isSameOrBefore(Moment|String|Number|Date|Array, String);

moment().isSameOrAfter(Moment|String|Number|Date|Array);
moment().isSameOrAfter(Moment|String|Number|Date|Array, String);