Dayjs – Getting started and common methods

Dayjs is a lightweight JavaScript library that handles times and dates

The official making github.com/iamkun/dayj…

Chinese usage document github.com/iamkun/dayj…

Dayjs benefits

• 🕒 and moment.js share the same API and schema
• 💪 immutable and persistent
• 🔥 provides chained calls
• 🌐 International standards
• 📦 ultra-small compression volume, only about 2KB
• 👫 most browsers are compatible

Dayjs installation

npm install dayjs --save
import dayjs from 'dayjs'
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<script src="https://unpkg.com/dayjs"></script>
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The return values of day.js are all new Dayjs objects

Dayjs parses the relevant API

Run dayjs() directly to get the dayJS object containing the current time and date

dayjs()  // Return current time Tue, 28 May 2019 05:57:34 GMT
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It is possible to parse a standard ISO 8601 time string passed in.

dayjs('1995-12-25') //Sun, 24 Dec 1995 16:00:00 GMT
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You can parse a Javascript Date object passed in.

dayjs(new Date(2018, 8, 18)) //Mon, 17 Sep 2018 16:00:00 GMT
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You can parse an incoming Unix timestamp (13 digits).

dayjs(1318781876406) //Sun, 16 Oct 2011 16:17:56 GMT
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Dayjs objects are immutable. If you want to get a copy of the object, execute.clone(). Passing a dayJS object to dayjs() will do the same.

dayjs(Dayjs)
dayjs().clone()
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Checks whether the current Dayjs object is a valid time

dayjs().isValid()
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Dayjs gets and sets the relevant API

Gets or sets the year.

dayjs().year() //2019
dayjs().year(2000) //Sun, 28 May 2000 06:14:07 GMT
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Gets or sets the month. Starting from 0

Dayjs ().month() //4 actually May dayjs(). Month (0) //Mon, 28 Jan 2019 06:15:25 GMTCopy the code

Gets or sets the date. Starting from 1

Dayjs ().date() //28 Dayjs (). Date (1) // May 2019 06:17:04 GMTCopy the code

Gets or sets the week. It starts at 0 on Sunday

Dayjs ().day() //2 It is Tuesday dayjs().day(0) //Sun, 26 May 2019 06:18:13 GMT is forcibly set to SundayCopy the code

Gets or sets the hour

Hour (12) //Tue, 28 May 2019 04:21:30 GMT UnclearCopy the code

Gets or sets the minutes.

dayjs().minute() //22 
dayjs().minute(59) //Tue, 28 May 2019 06:59:50 GMT
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Gets or sets seconds

dayjs().millisecond()
dayjs().millisecond(1)
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Gets or sets milliseconds.

dayjs().millisecond()
dayjs().millisecond(1)
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The unit passed in to get the information taken from the Dayjs object is case insensitive

dayjs().get('month') //4
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Set a time

dayjs().set('date'.1);
dayjs().set('month'.3); / / April
dayjs().set('second'.30);
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Apis for dayJS operations

You can add or subtract the Dayjs objects as follows

Increments the time and returns a new Dayjs() object.

dayjs().add(value : Number, unit : String); dayjs().add(7, 'day'); // Add 7 days to the current numberCopy the code

Reduces the time and returns a new Dayjs() object.

dayjs().subtract(value : Number, unit : String); dayjs().subtract(7, 'day'); // Reduce 7 days from the current levelCopy the code

Returns the Dayjs() object for the beginning of the current time, such as the first day of the month.

dayjs().startOf(unit : String);
dayjs().startOf('month'); //Tue, 30 Apr 2019 16:00:00 GMT 
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Dayjs() object that returns the end time of the current time, such as the last day of the month.

dayjs().endOf(unit : String);
dayjs().endOf('month'); //Fri, 31 May 2019 15:59:59 GMT
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Display relevant apis

Format the Dayjs object and display it.

Receives a series of time and date strings and replaces them with the corresponding values.

dayjs().format(String)
dayjs('2019-01-25').format('YYYY-MM-DD HH:mm:ss') 
dayjs().format('YYYY-MM-DD') 
dayjs().format('YYYY-MM') //2019
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Gets the time difference between two Dayjs objects, milliseconds by default.

const date1 = dayjs('2019-01-25')
const date2 = dayjs('2018-06-05')
date1.diff(date2) // 20214000000
date1.diff(date2, 'month') // 7
date1.diff(date2, 'month', true) // 7.645161290322581
date1.diff(date2, 'day') // 233
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Return Unix timestamp (ms)

dayjs().valueOf()
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Returns the Unix timestamp in seconds.

dayjs().unix()
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Returns the number of days in the month

dayjs().daysInMonth()
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Returns a native Date object.

dayjs().toDate()
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When serializing a Dayjs object, a string in ISO8601 format is returned.

Dayjs (). The toJSON () / / "the 2018-08-08 T00:00:00. 000 z"Copy the code

The value is a string in ISO8601 format.

dayjs().toISOString()
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Return string

dayjs().toString()
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Query the relevant API to check whether one Dayjs object precedes another Dayjs object.

dayjs().isBefore(Dayjs, unit? : String);
dayjs().isBefore(dayjs()); // false
dayjs().isBefore(dayjs(), 'year'); // false
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Check if one Dayjs object is at the same time as another Dayjs object.

dayjs().isSame(Dayjs, unit? : String);
dayjs().isSame(dayjs()); // true
dayjs().isSame(dayjs(), 'year'); // true
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Check if one Dayjs object is after another Dayjs object.

dayjs().isAfter(Dayjs, unit? : String);
dayjs().isAfter(dayjs()); // false
dayjs().isAfter(dayjs(), 'year'); // false
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