date-diff.ts 的修订

1 file changed, 52 insertions

date-diff.ts(文件已创建)

		@@ -0,0 +1,52 @@
1	+	const calcDateDifference = (
2	+	start: string \| Date,
3	+	end: string \| Date,
4	+	): { year: number; month: number; day: number } => {
5	+	// Convert to true dates without time
6	+	let startDate = new Date(new Date(start).toISOString().substring(0, 10));
7	+	let endDate = new Date(
8	+	(end ? new Date(end) : new Date()).toISOString().substring(0, 10),
9	+	);
10	+
11	+	// If start date comes after end, flip them around
12	+	if (startDate > endDate) {
13	+	const swap = startDate;
14	+	startDate = endDate;
15	+	endDate = swap;
16	+	}
17	+
18	+	// Account for leap years
19	+	const startYear = startDate.getFullYear();
20	+	const february =
21	+	(startYear % 4 === 0 && startYear % 100 !== 0) \|\| startYear % 400 === 0
22	+	? 29
23	+	: 28;
24	+	const daysInMonth = [31, february, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
25	+
26	+	// Create year and month diffs
27	+	let yearDiff = endDate.getFullYear() - startYear;
28	+	let monthDiff = endDate.getMonth() - startDate.getMonth();
29	+	if (monthDiff < 0) {
30	+	yearDiff--;
31	+	monthDiff += 12;
32	+	}
33	+
34	+	// Create day diff while adjusting others
35	+	let dayDiff = endDate.getDate() - startDate.getDate();
36	+	if (dayDiff < 0) {
37	+	if (monthDiff > 0) {
38	+	monthDiff--;
39	+	} else {
40	+	yearDiff--;
41	+	monthDiff = 11;
42	+	}
43	+	dayDiff += daysInMonth[startDate.getMonth()];
44	+	}
45	+
46	+	// Return true differentials
47	+	return {
48	+	year: yearDiff,
49	+	month: monthDiff,
50	+	day: dayDiff,
51	+	};
52	+	}