快速解析JSON数组，对其进行排序并找到重叠的日期

Question

我该如何解析？数组未命名，对象未命名？如果你们也有任何建议，我也需要对它进行排序并找到事件之间的重叠（确定冲突），这对我也将是巨大的帮助。

[{"title": "Evening Picnic", "start": "November 10, 2018 6:00 PM", "end": "November 10, 2018 7:00 PM"}, {"title": "Nap Break", "start": "November 8, 2018 12:56 PM", "end": "November 8, 2018 1:30 PM"}, {"title": "Football Game", "start": "November 3, 2018 6:14 PM", "end": "November 3, 2018 9:44 PM"}, {"title": "Evening Cookout with Friends", "start": "November 6, 2018 5:00 PM", "end": "November 6, 2018 10:00 PM"}, {"title": "Roller Derby", "start": "November 7, 2018 12:00 PM", "end": "November 7, 2018 2:30 PM"}, {"title": "Basketball Game", "start": "November 8, 2018 7:30 PM", "end": "November 8, 2018 10:30 PM"}, {"title": "Local Pub with Friends", "start": "November 1, 2018 7:33 PM", "end": "November 1, 2018 11:00 PM"}, {"title": "Dentist Appointment", "start": "November 10, 2018 1:45 PM", "end": "November 10, 2018 2:30 PM"}, {"title": "Volleyball With Friends", "start": "November 6, 2018 12:00 PM", "end": "November 6, 2018 1:26 PM"}, {"title": "Free Donuts", "start": "November 9, 2018 3:00 PM", "end": "November 9, 2018 4:00 PM"}, {"title": "TV Show Marathon", "start": "November 9, 2018 4:30 PM", "end": "November 9, 2018 9:00 PM"}, {"title": "Boba Tea Grand Opening", "start": "November 6, 2018 1:27 PM", "end": "November 6, 2018 2:00 PM"}, {"title": "Lunch with Friends", "start": "November 8, 2018 11:30 AM", "end": "November 8, 2018 12:59 PM"}, {"title": "SF Coffee Festival","start": "November 6, 2018 6:00 PM","end": "November 6, 2018 9:00 PM"}, {"title": "Beer with Friends", "start": "November 9, 2018 8:00 PM", "end": "November 9, 2018 9:30 PM"}, {"title": "Yoga", "start": "November 1, 2018 6:00 PM", "end": "November 1, 2018 7:33 PM"}, {"title": "Rock Concert", "start": "November 7, 2018 6:30 PM", "end": "November 7, 2018 11:00 PM"}, {"title": "Lunch Meeting", "start": "November 9, 2018 12:30 PM", "end": "November 9, 2018 2:30 PM"}, {"title": "Bicycling with Friends", "start": "November 1, 2018 6:00 AM", "end": "November 1, 2018 9:30 AM"}, {"title": "Birthday Party", "start": "November 10, 2018 12:30 PM", "end": "November 10, 2018 8:30 PM"}, {"title": "Football Tailgate with John", "start": "November 3, 2018 6:14 PM", "end": "November 3, 2018 9:44 PM"}]   

我是新手，我想知道如何处理此问题

Answer 1

考虑到这是您先前的post中的跟进问题。您可以使用Swift DateInterval初始化程序创建带有DateInverval和start日期的end，并检查它们是否相互交叉：

extension Event {
    var interval: DateInterval { .init(start: start, end: end) }
    func intersects(with event: Event) -> Bool { interval.intersects(event.interval) }
}

---

要检查有冲突的事件，您需要使您的事件符合Equatable并过滤与它们相交但不是同一事件的事件：

struct Event: Codable, Equatable {
    let title: String
    let start: Date
    let end: Date
}

---

let decoder = JSONDecoder()
decoder.dateDecodingStrategy = .monthDayYearTime
do {
    let events = try decoder.decode([Event].self, from: Data(json.utf8))
    print(events.sorted())
    let conflictingEvents: [(Event, Event)] = events.compactMap {
        for event in events where event != $0 {
            if event.intersects(with: $0) && $0.end != event.start && event.end != $0.start { return ($0, event) }
        }
        return nil
    }
    print(events.count)             // "21\n"
    print(conflictingEvents.count)  // "11\n"
} catch {
    print(error)
}

Answer 2

您的JSON结构只有两个“难”的地方，可能会使它在工作中抛出扳手。

事实就是它是一个简单的JSON数组和非标准的日期格式。

[我建议从一个好的教程开始，像Ultimate Guide to JSON Parsing with Swift，它可能是实际的来源，因为它涵盖了我迄今为止必须使用的几乎所有用例。

首先定义一个保存基本数据并符合Codable协议的结构

struct Event: Codable {
    let title: String
    let end: Date
    let start: Date
}

创建JSONDecoder并为其提供自定义dateDecodingStrategy

let formatter = DateFormatter()
formatter.dateFormat = "MMMM dd, yyyy hh:mm a"

let decoder = JSONDecoder()
decoder.dateDecodingStrategy = .formatted(formatter)

您需要将JSON响应转换为Data。我可能已经是这种格式，或者您可以直接转换String文本，这是我为测试所做的]

let formatter = DateFormatter()
formatter.dateFormat = "MMMM dd, yyyy hh:mm a"
formatter.locale = Locale(identifier: "en_US_POSIX")

let decoder = JSONDecoder()
decoder.dateDecodingStrategy = .formatted(formatter)

最后，解码响应...

let events = try decoder.decode([Event].self, from: data)

从那里您可以开始处理数据。

排序数组和日期比较是一个很容易回答的问题，只有这么多示例可供选择，在这里我不再尝试重复。做一些研究，尝试一些想法。如果您仍然遇到问题，请作为另一个（重点突出的）问题，并提供尝试的机会