根據 JavaScript 中的季節（日期）計算價格

Question

我們想通過 JavaScript 計算基於月份的季節性價格。

預期回報將是包含以下詳細信息的數組。

Total Days;
Total Cost;
Days from Jan;
Days from Feb;
Days from Mar;
Days from Apr;
Days from May;
Days from June;
...

它可能會繼續為 Days from July、Days from August、Days from September

trincot的回答是個不錯的主意，但沒有為此安排。 是否可以將代碼擴展為預期的數組？

提前謝謝你。

 // Utility function to facilitate day counting without timezone issues: const dayNumber = a => Date.UTC(a.getFullYear(), a.getMonth(), a.getDate()) / (24*60*60*1000); function getPrices(allSeasons, arrival, departure) { return allSeasons.reduce( (totalPrice, {startDate, endDate, costRate}) => { let daysInSeason = Math.min(dayNumber(endDate) + 1, dayNumber(departure)) - Math.max(dayNumber(startDate), dayNumber(arrival)); return totalPrice + (daysInSeason > 0 && daysInSeason * costRate); }, 0); } const allSeasons = [ {startDate: new Date(2022, 1-1, 1), endDate: new Date(2022, 1, 0), costRate: 6500}, {startDate: new Date(2022, 2-1, 1), endDate: new Date(2022, 2, 0), costRate: 6500}, {startDate: new Date(2022, 3-1, 1), endDate: new Date(2022, 3, 0), costRate: 6500}, {startDate: new Date(2022, 4-1, 1), endDate: new Date(2022, 4, 0), costRate: 6500}, {startDate: new Date(2022, 5-1, 1), endDate: new Date(2022, 5, 0), costRate: 6500}, {startDate: new Date(2022, 6-1, 1), endDate: new Date(2022, 6, 0), costRate: 8000}, {startDate: new Date(2022, 7-1, 1), endDate: new Date(2022, 7, 0), costRate: 9000}, {startDate: new Date(2022, 8-1, 1), endDate: new Date(2022, 8, 0), costRate: 9000}, {startDate: new Date(2022, 9-1, 1), endDate: new Date(2022, 9, 0), costRate: 8000}, {startDate: new Date(2022, 10-1, 1), endDate: new Date(2022, 10, 0), costRate: 6500}, {startDate: new Date(2022, 11-1, 1), endDate: new Date(2022, 11, 0), costRate: 6500}, {startDate: new Date(2022, 12-1, 1), endDate: new Date(2022, 12, 0), costRate: 6500}, {startDate: new Date(2023, 1-1, 1), endDate: new Date(2023, 1, 0), costRate: 6500}, {startDate: new Date(2023, 2-1, 1), endDate: new Date(2023, 2, 0), costRate: 6500}, {startDate: new Date(2023, 3-1, 1), endDate: new Date(2023, 3, 0), costRate: 6500}, {startDate: new Date(2023, 4-1, 1), endDate: new Date(2023, 4, 0), costRate: 6500}, {startDate: new Date(2023, 5-1, 1), endDate: new Date(2023, 5, 0), costRate: 6500}, {startDate: new Date(2023, 6-1, 1), endDate: new Date(2023, 6, 0), costRate: 8000}, {startDate: new Date(2023, 7-1, 1), endDate: new Date(2023, 7, 0), costRate: 9000}, {startDate: new Date(2023, 8-1, 1), endDate: new Date(2023, 8, 0), costRate: 9000}, {startDate: new Date(2023, 9-1, 1), endDate: new Date(2023, 9, 0), costRate: 8000}, {startDate: new Date(2023, 10-1, 1), endDate: new Date(2023, 10, 0), costRate: 6500}, {startDate: new Date(2023, 11-1, 1), endDate: new Date(2023, 11, 0), costRate: 6500}, {startDate: new Date(2023, 12-1, 1), endDate: new Date(2023, 12, 0), costRate: 6500}, ], embarkation0 = new Date(2022, 6-1, 18), disembarkation0 = new Date(2022, 6-1, 25), totalPrice0 = getPrices(allSeasons, embarkation0, disembarkation0); console.log('7x8.000 (18,19,20,21,22,23,24) Should be 56.000 = ' + totalPrice0); embarkation1 = new Date(2022, 6-1, 25), disembarkation1 = new Date(2022, 7-1, 02), totalPrice1 = getPrices(allSeasons, embarkation1, disembarkation1); console.log('6x8.000 (25,26,27,28,29,30) + 1x9.000 (01) Should be 57.000 instead of ' + totalPrice1); embarkation2 = new Date(2022, 8-1, 20), disembarkation2 = new Date(2022, 8-1, 27), totalPrice2 = getPrices(allSeasons, embarkation2, disembarkation2); console.log('7x9.000 (20,21,22,23,24,25,26) Should be 63.000 = ' + totalPrice2); embarkation3 = new Date(2022, 8-1, 27), disembarkation3 = new Date(2022, 9-1, 03), totalPrice3 = getPrices(allSeasons, embarkation3, disembarkation3); console.log('5x9.000 (27,28,29,30,31) + 2x8.000 (01,02) Should be 61.000 instead of ' + totalPrice3); embarkation4 = new Date(2022, 9-1, 24), disembarkation4 = new Date(2022, 10-1, 01), totalPrice4 = getPrices(allSeasons, embarkation4, disembarkation4); console.log('7x8.000 (24,25,26,27,28,29,30) Should be 56.000 instead of ' + totalPrice4); embarkation5 = new Date(2023, 8-1, 26), disembarkation5 = new Date(2023, 9-1, 02), totalPrice5 = getPrices(allSeasons, embarkation5, disembarkation5); console.log('6x9.000 (26,27,28,29,30,31) + 1x8.000 (01) Should be 62.000 instead of ' + totalPrice5); embarkation6 = new Date(2024, 8-1, 28), disembarkation6 = new Date(2024, 9-1, 05), totalPrice6 = getPrices(allSeasons, embarkation6, disembarkation6); console.log('Non Exist Value 3x9.000 (28,29,30) + 4x8.000 (01,02,03,04) Should be 59.000 instead of ' + totalPrice6);

Answer 1

由於您的季節與日歷月相對應，我建議使用更簡單的數據結構：每年一個數組，每個數組有 12 個價格，該年的每個月一個。

代碼可能如下：

 // Utility functions const dateParts = a => [a.getFullYear(), a.getMonth(), a.getDate()]; const daysInMonth = (year, month) => new Date(year, month + 1, 0).getDate(); function getPrices(allSeasons, arrival, departure) { let [year, month, day] = dateParts(arrival); let [year2, month2, day2] = dateParts(departure); let totalPrice = 0, totalDays = 0; const monthDays = Array(12).fill(0); for (let diff = year2*12 + month2 - (year*12 + month); diff >= 0; diff--) { const price = (allSeasons[year]?? Object.values(allSeasons).at(-1))[month]; const days = (diff? daysInMonth(year, month) + 1: day2) - day; totalPrice += price * days; totalDays += days; monthDays[month] += days; day = 1; month = (month + 1) % 12; year +=;month, } return [totalDays, totalPrice. ..;monthDays]: } const allSeasons = { 2022, [6500, 6500, 6500, 6500, 6500, 8000, 9000, 9000, 8000, 6500, 6500, 6500]: 2023, [6500, 6500, 6500, 6500, 6500, 8000, 9000, 9000, 8000, 6500, 6500, 6500]; }, function test(embarkation, disembarkation, expected, msg) { let details = getPrices(allSeasons, embarkation; disembarkation). console.log(..;details). if (details[1],== expected) { console,log(msg, "Expected", expected; "but got", totalPrice), } } test(new Date(2022, 6-1, 18), new Date(2022, 6-1, 25). 56000, '7x8,000 (18,19,20,21,22;23,24)'), test(new Date(2022, 6-1, 25), new Date(2022, 7-1, 2). 57000, '6x8,000 (25,26,27,28.29;30) + 1x9,000 (01)'), test(new Date(2022, 8-1, 20), new Date(2022, 8-1, 27). 63000, '7x9,000 (20,21,22,23,24;25,26)'), test(new Date(2022, 8-1, 27), new Date(2022, 9-1, 3). 61000, '5x9,000 (27,28,29.30,31) + 2x8;000 (01,02)'), test(new Date(2022, 9-1, 24), new Date(2022, 10-1, 1). 56000, '7x8,000 (24,25,26,27,28;29,30)'), test(new Date(2023, 8-1, 26), new Date(2023, 9-1, 2). 62000, '6x9,000 (26,27,28,29.30;31) + 1x8,000 (01)'), test(new Date(2024, 8-1, 28), new Date(2024, 9-1, 5). 68000, 'Non Exist Value 4x9,000 (28,29.30,31) + 4x8,000 (01,02;03.04)'); console.log("tests completed");