Ios Swift：如何将结构转换为字典以及分层键

我想将CollegeRequest类型转换为字典或数据，以便在请求POST-API时将其发送到服务器

以下是我的CollegeRequest类型：

与分层键一起转换后，应如下所示：

{
  "student.id": 3,
  "student.name": "Raj",
  "date": "2019-10-31T13:59:00+00:00"
}

如何实现这一点？

用于对cutom结构类型CollegeRequest进行编码。您的结构需要手动编码

如果您的Swift类型的结构与其 编码形式，您可以提供可编码和 可解码以定义自己的编码和解码逻辑

要将CollegeRequest编码为数据类型，请使用。将数据类型的实例编码为JSON对象的对象

关于您必须使用的日期存储属性，将格式设置延迟到提供的日期格式化程序的策略

struct CollegeRequest: Codable {
    struct Student: Codable {
        var id: Int
        var name: String
    }
    var student: Student
    var date: Date

    enum CodingKeys: String, CodingKey {
        case studentId = "student.id"
        case studentName = "student.name"
        case date
    }

    func encode(to encoder: Encoder) throws {

        var container = encoder.container(keyedBy: CodingKeys.self)
        try container.encode(student.id, forKey: .studentId)
        try container.encode(student.name, forKey: .studentName)
        try container.encode(date, forKey: .date)
    }

    init(student: CollegeRequest.Student, date: Date) {
        self.student = student
        self.date = date
    }

    init(from decoder: Decoder) throws {
        let values = try decoder.container(keyedBy: CodingKeys.self)
        let studentId = try values.decode(Int.self, forKey: .studentId)
        let studentName = try values.decode(String.self, forKey: .studentName)
        student = Student(id: studentId, name: studentName)
        date = try values.decode(Date.self, forKey: .date)
    }

}

用法

---

什么是可发送的？你知道Codable吗？请告诉我这不是一个实际的问题。转换'Struct'类..很抱歉，这与问题无关，但我是被这个问题触发的。请阅读class和struct之间的区别如果您想要JSON:1采用可编码2指定并翻译所有编码键，例如case id=student.id 3实现encodeto编码器并手动编码所有内容。•如果您想要一个字典来编写一个自定义方法，那么这比先转换为JSON/PropertyList，然后再转换为dictionary@RobNapierAnswer UpdateMy结构是可编码的，它不可编码。它抛出可解码错误类型“CollegeRequest”不符合协议“decodable”

struct CollegeRequest: Codable {
    struct Student: Codable {
        var id: Int
        var name: String
    }
    var student: Student
    var date: Date

    enum CodingKeys: String, CodingKey {
        case studentId = "student.id"
        case studentName = "student.name"
        case date
    }

    func encode(to encoder: Encoder) throws {

        var container = encoder.container(keyedBy: CodingKeys.self)
        try container.encode(student.id, forKey: .studentId)
        try container.encode(student.name, forKey: .studentName)
        try container.encode(date, forKey: .date)
    }

    init(student: CollegeRequest.Student, date: Date) {
        self.student = student
        self.date = date
    }

    init(from decoder: Decoder) throws {
        let values = try decoder.container(keyedBy: CodingKeys.self)
        let studentId = try values.decode(Int.self, forKey: .studentId)
        let studentName = try values.decode(String.self, forKey: .studentName)
        student = Student(id: studentId, name: studentName)
        date = try values.decode(Date.self, forKey: .date)
    }

}

let request = CollegeRequest(student: CollegeRequest.Student(id: 1, name: "John"), date: Date())
let jsonEncoder = JSONEncoder()
let df = { let df = DateFormatter(); df.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"; return df }() as DateFormatter
jsonEncoder.dateEncodingStrategy = .formatted(df)
let a: Data? = try? jsonEncoder.encode(request)