date.diff()

The diff method calculates the elapsed time duration between the current NepaliDate instance and another date object. It can return the difference in days, months, years, hours, minutes, seconds, or milliseconds, making it suitable for calculating age, tenure, or interval durations.

ImportCopy Anchor Link

import { NepaliDate } from "nepali-date-library";

SignatureCopy Anchor Link

diff(date: NepaliDate, unit: "year" | "month" | "day"): number;

ParametersCopy Anchor Link

Return ValueCopy Anchor Link

• Type: number
• The numeric difference between the two dates (this - date).
• Positive if the current date is after date.
• Negative if the current date is before date.
• Zero if they are identical in the evaluated unit.

Calculation RulesCopy Anchor Link

• "day": Computed using Unix timestamps: Math.floor((this.getTime() - date.getTime()) / 86400000).
• "month": Computed using calendar month indices: (this.year - date.year) * 12 + (this.month - date.month).
• "year": Computed by year difference: this.year - date.year.

ExceptionsCopy Anchor Link

Throws an Error if an invalid unit string is supplied:

"Invalid unit for diff calculation"

ExamplesCopy Anchor Link

Difference in DaysCopy Anchor Link

import { NepaliDate } from "nepali-date-library";

const date1 = new NepaliDate("2081-01-20");
const date2 = new NepaliDate("2081-01-05");

console.log(date1.diff(date2, "day")); // 15
console.log(date2.diff(date1, "day")); // -15

Difference in MonthsCopy Anchor Link

import { NepaliDate } from "nepali-date-library";

const date1 = new NepaliDate("2081-06-15");
const date2 = new NepaliDate("2080-04-15");

console.log(date1.diff(date2, "month")); // 14

Difference in YearsCopy Anchor Link

import { NepaliDate } from "nepali-date-library";

const date1 = new NepaliDate("2085-01-01");
const date2 = new NepaliDate("2081-01-01");

console.log(date1.diff(date2, "year")); // 4

RelatedCopy Anchor Link

• date.isBefore(): Check if a date precedes another.
• date.isAfter(): Check if a date succeeds another.
• date.isEqual(): Check if two dates are equal.