A simple and easy to use JavaScript library that provides common calendar functionalities for making completely customizable calendar UI. Based heavily on the work done by https://github.com/ashutoshbw/headless-calendar
- It does all the calculations for finding the position of a day in a calendar.
- A calendar is an iterable. So you can use
for ofloop or the spread syntax to easily iterate over the days. - You can choose which day to start a week with.
- Provides handy calendar classes for generating calendar of any month, year, last year or any period of time supported by original JavaScript Date object.
- It is based on original JavaScript
Datebut provides an abstraction over by excluding all the parts that doesn't needed or are not intuitive.
N/A for now
| Classes | Description |
|---|---|
Calendar |
It is the generic class for generating any arbitrary calendar from any date to any future date. |
CalendarOfMonth |
It generates calendar of any given month. |
CalendarOfYear |
It generates calendar of any given year. |
PlainDate |
It is a simple wrapper around the JavaScript Date. You can use it to find the difference between two dates, next, previous days and some other helpful things. |
You can fetch the above classes using both ES6 and CommonJS module syntax.
To understand how to use headless-calendar effectively, it will be helpful to picture a calendar as a two dimensional diagram like below:
+-------------------------> Day Axis
| 0 1 2 3 4 5 6 ---> Day Axis indices. Starts with 0.
| V V V V V V V
| Su Mo Tu We Th Fr Sa ---> Day Names
| 1 2 3 4 ---> 0
| 5 6 7 8 9 10 11 ---> 1
| 12 13 14 15 16 17 18 ---> 2
| 19 20 21 22 23 24 25 ---> 3
| 26 27 28 29 30 31 ---> 4
| |
V V
Week Axis Week Axis indices. Starts with 0 too.
import {CalendarOfMonth} from "@onsetsoftware/headless-calendar";
// generates the calendar of January of 2021
const month = new CalendarOfMonth(2021, 1);
for (day of month) {
console.log(day);
}
/*
Day {
date: PlainDate { year: 2021, month: 1, date: 1 },
dayNumber: 1, // it counts the day
dayOfTheWeek: 1, // the day of the week from 0-6 = Sun - Sat
dayAxisIndex: 5, // the day axis index as explained in the above diagram
weekAxisIndex: 0 // the week axis index as explained in the above diagram
}
.
.
.
*/The day object holds the necessary information about it's position on the calendar. This pattern of accessing days are same for all the calendar classes.
And as any calendar is an iterable you can also use it like below:
// console logs only dates that are Sundays
[...month].forEach(day => {
if (day.dayAxisIndex == 0) {
console.log(day.date.date);
}
})This class is used to generate a calendar starting with any date to any future date. All the other calendar classes are derived from it.
Syntax:
new Calendar(startDateString, endDateString, [startWeekDayIndex])
startDateString(String) andendDateString(String): They should follow the formatyear-month-dateformat. Each part is expressed with digits.endDateStringmust represent a equal or later date thanstartDateString.startWeekDayIndex(Number) Optional: It represents the day to start the week with.0means Sunday and it goes on incrementally until 6 means Saturday.
An iterable object. It has the following properties:
startDate: It is thePlainDateversion of starting date.endDate: It is thePlainDateversion of ending date.startWeekDayIndex: It keeps record of thestartWeekDayIndexparameters value. It that is not provided it defaults to zero.maxWeekAxisIndex: This returns last week's week axis index.weekDayNames: It returns an array of day names with the starting day as you specified with thestartWeekDayIndexparameter.length: It returns the number total days in the calendar.
And it has a toString() method for easily seeing the output of a calendar. For example:
import {Calendar} from "@onsetsoftware/headless-calendar";
const cal = new Calendar("2021-1-1", "2021-2-10");
console.log(cal.toString());
/*
Su Mo Tu We Th Fr Sa
1 2 January 2021
3 4 5 6 7 8 9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
31 1 2 3 4 5 6 February
7 8 9 10
*/The iterable is used to iterate over the days of the calendar. Each item of the sequence of this iterable is an object that represents a day. These day objects comes with the following properties and methods:
date: APlainDaterepresenting that day.dayNumber: If it is n, it means it's the nth day of the calendar.dayOfTheWeek: the number 0-6 indicating Sunday (0) - Saturday (6).dayAxisIndex: It is the day axis index of the day as shown in diagram.weekAxisIndex: It is the week axis index of the day as shown in diagram.
isFirstDayOfWeekAndMonth(): It returns a Boolean value indicating if the day is the 1st day of the week and also the 1st day of the month. This value is useful if you want to show month names right above such days.
This class is used to generate a calendar of the specified month.
Syntax:
new CalendarOfMonth(year, month, [startWeekDayIndex])
year(Number) andmonth(Number): The year and month number for generating the calendar. Note that unlike in JavaScript, here month starts with1(January).startWeekDayIndex(Number) Optional: It represents the day to start the week with.0means Sunday and it goes on incrementally until 6 means Saturday.
An iterable object with the same interface of a Calendar instance representing the days of the specified month.
It's toString() method formats the calendar a little differently than the original Calendar class:
import {CalendarOfMonth} from "@onsetsoftware/headless-calendar";
const month = new CalendarOfMonth(2021, 1);
console.log(month.toString())
/*
January 2021
Su Mo Tu We Th Fr Sa
1 2
3 4 5 6 7 8 9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
31
*/This class is used to generate a calendar of the given year.
Syntax:
new CalendarOfYear(year, [startWeekDayIndex])
year(Number): The year number for generating the calendar.startWeekDayIndex(Number) Optional: It represents the day to start the week with.0means Sunday and it goes on incrementally until 6 means Saturday.
An iterable object with the same interface of a Calendar instance, representing the days of the specified year.
PlainDate is wrapper class around the original JavaScript Date. It only thinks about year, month and date. No hours, minutes or others parts.
Syntax:
new PlainDate(dateString: DateString, locale?: Intl.LocalesArgument)
dateString(String) Optional: It should follow the formatyear-month-dateformat. Each part is expressed with digits. If it is omitted, it is treated as current date according to local time.
An instance of PlainDate. It it only has three properties year, month and date holding the corresponding given information.
A PlainDate instance has the following methods:
It converts a PlainDate to JavaScript date.
Syntax:
somePlainDate.toJSDate()No parameter
JavaScript version of the PlainDate.
Checks whether two PlainDates are equal or not.
Syntax:
somePlainDate.equals(another)another(PlainDate): AnotherPlainDatevalue to compare to.
A Boolean value indicating whether the PlainDate equals another PlainDate.
Checks whether the given PlainDate is before the current one.
Syntax:
somePlainDate.isBefore(another)another(PlainDate): AnotherPlainDatevalue to compare to.
A Boolean value indicating whether the PlainDate is before another PlainDate.
Checks whether the given PlainDate is after the current one.
Syntax:
somePlainDate.isBefore(another)another(PlainDate): AnotherPlainDatevalue to compare to.
A Boolean value indicating whether the PlainDate is after another PlainDate.
Returns the difference between two PlainDates.
Syntax:
somePlainDate.diff(another);
another(PlainDate): AnotherPlainDatevalue to find the difference.
The difference between the two PlainDates. Note that the boundary dates are included in the counting.
Returns the next PlainDate.
Syntax:
somePlainDate.next();
None.
The next PlainDate.
Returns the previous PlainDate.
Syntax:
somePlainDate.previous();
None.
The previous PlainDate.
Returns the day days after the active PlainDate.
Syntax:
somePlainDate.addDays(days);
days(number): The number of days to add
The PlainDate days after the active date.
Returns the day days before the active PlainDate.
Syntax:
somePlainDate.subDays(days);
days(number): The number of days to subtract
The PlainDate days before the active date.
A string representation of the PlainDate as a DateString.
Syntax:
somePlainDate.toString();
None.
A string representation of somePlainDate with the year-month-date format where each part is made of digits. year is full year.
Returns a plain date from a JavaScript date.
Syntax:
PlainDate.fromJSDate(date, [UTC])date(Date): A JavaScriptDateinstance.UTC(Boolean) Optional: By default it istrue, that means the date is treated as UTC time. If you want local time, set it tofalse.
The PlainDate version of the JavaScript date according to UTC or local time(based on the 2nd parameter).
Returns today in PlainDate.
Syntax:
PlainDate.today([UTC])UTC(Boolean) Optional: By default it istrue, that means we will get result in UTC time. If you want local time set it tofalse.
Today in PlainDate according local time or UTC time(based on the 1st parameter).
MIT