SWIFT4.1 JSON到Struct然后到不同日期的数组

Question

我正在调用一个API，它返回约会的JSON结果。示例：

[{"DiarySummary":"Test appointment","DiaryDescription":"Test","DiaryId":"62","EventNo":"","EventTypeId":"","StartDateTime":"07/06/2018 09:00:51","StopDateTime":"07/06/2018 21:00:51","DayHalfDay":"0","AgentGroupName":"DEV","AgentInitials":"AC","AgentId":"5","OwnerShortName":"","OwnerLongName":"","AbsenceTypeDescription":"Working From Home","AbsenceTypeId":"15"}...

我使用解码函数将这个映射映射到代码中的一个结构：

struct DiaryAppointment: Decodable {
let DiarySummary: String?
let DiaryDescription: String?
let DiaryId: String?
let EventNo: String?
let EventTypeId: String?
let StartDateTime: String?
let StopDateTime: String?
let DayHalfDay: String?
let AgentGroupName: String?
let AgentInitials: String?
let AgentId: String?
let OwnerShortName: String?
let OwnerLongName: String?
let AbsenceTypeDescription: String?
let AbsenceTypeId: String?
}

self.appointments = try JSONDecoder().decode([DiaryAppointment].self, from: data!)

然后，self.appointments数组在UICollectionView中使用。所有这些都很好。但是，我想将collectionView分割成基于不同StartDates的部分，每个节都有一个头。

我尝试过创建一个辅助数组，但是在我的JSON中，以及在约会数组中，StartDateTime的值是一个字符串，而不是日期。我可以循环遍历约会数组，并将appointment.StartDateTime的值转换为date对象，并添加到一个新的数组中，该数组应该允许我选择不同的日期，但是我无法拆分原始约会数组，因为该值仍然是一个字符串。

是否有可能在调用解码时将其转换为date对象？如果没有，我如何实现所需的功能，或者，是否有更好的方法来做到这一点？

Answer 1

首先，使用CodingKeys获取小写变量名，并尽可能多地声明非可选属性：

struct DiaryAppointment: Decodable {
    private enum CodingKeys: String, CodingKey {
        case diarySummary = "DiarySummary", diaryDescription = "DiaryDescription", diaryId = "DiaryId"
        case eventNo = "EventNo", eventTypeId = "EventTypeId", startDateTime = "StartDateTime"
        case stopDateTime = "StopDateTime", dayHalfDay = "DayHalfDay", agentGroupName = "AgentGroupName"
        case agentInitials = "AgentInitials", agentId = "AgentId", ownerShortName = "OwnerShortName"
        case ownerLongName = "OwnerLongName", absenceTypeDescription = "AbsenceTypeDescription", absenceTypeId = "AbsenceTypeId"
    }
    let diarySummary, diaryDescription, diaryId, eventNo, eventTypeId: String
    let startDateTime, stopDateTime: Date
    let dayHalfDay, agentGroupName, agentInitials, agentId: String
    let ownerShortName, ownerLongName, absenceTypeDescription, absenceTypeId: String
}

声明startDateTime和stopDateTime为Date，并将DateFormatter传递为dateDecodingStrategy

let decoder = JSONDecoder()
let dateFormatter = DateFormatter()
dateFormatter.locale = Locale(identifier: "en_US_POSIX")
dateFormatter.dateFormat = "dd/MM/yyyy HH:mm:ss"
decoder.dateDecodingStrategy = .formatted(dateFormatter)