swift 自带序列化，以及加强操作

swift本身支持对象和结构体的json了，不想在集成各种库的话你可以试试CodaBle来json格式化结构体和自定义的对象
将学会如何使用扩展的方式 如何实现一套 嵌套 数组和字典 属性的全属性完全序列化

struct Cat: Codable {
    let name: String
    let age: Int
}

let kitten = Cat(name: "kitten", age: 2)
let encoder = JSONEncoder()

do {
    let data = try encoder.encode(kitten)
    _ = try JSONSerialization.jsonObject(with: data, options: [])
    
    // ["name": "kitten", "age": 2]
} catch {
    print(error)
}


struct ACat {
    let name: String
    let age: Int
}




let akitten = ACat(name: "kitten", age: 2)
let mirror = Mirror(reflecting: akitten)
for child in mirror.children {
    print("\(child.label!) - \(child.value)")
}







protocol DictionaryValue {
    var value: Any { get }
}
extension Int: DictionaryValue { var value: Any { return self } }
extension Float: DictionaryValue { var value: Any { return self } }
extension String: DictionaryValue { var value: Any { return self } }
extension Bool: DictionaryValue { var value: Any { return self } }


//extension Array: DictionaryValue where Element: DictionaryValue {
//    var value: Any { return map { $0.value } }
//}
//
//extension Dictionary: DictionaryValue where Value: DictionaryValue {
//    var value: Any { return mapValues { $0.value } }
//}
//让本身也支持  array 和 Dictionary类型的也支持
extension Array: DictionaryValue {
    var value: Any { return map { ($0 as! DictionaryValue).value } }
}
extension Dictionary: DictionaryValue {
    var value: Any { return mapValues { ($0 as! DictionaryValue).value } }
}

extension DictionaryValue {
    var value: Any {
        let mirror = Mirror(reflecting: self)
        var result = [String: Any]()
        for child in mirror.children {
            // 如果无法获得正确的 key，报错
            guard let key = child.label else {
                fatalError("Invalid key in child: \(child)")
            }
            // 如果 value 无法转换为 DictionaryValue，报错
            if let value = child.value as? DictionaryValue {
                result[key] = value.value
            } else {
                fatalError("Invalid value in child: \(child)")
            }
        }
        return result
    }
}

struct CCat: DictionaryValue {
    let name: String
    let age: Int
}

let Ckitten = CCat(name: "kitten", age: 2)
print(Ckitten.value)




struct Wizard: DictionaryValue {
    let name: String
    let cat:CCat
}

let wizard = Wizard(name: "Hermione", cat: Ckitten)
print(wizard.value) //嵌套自定义的对象也能完整序列化


struct Gryffindor: DictionaryValue {
    let wizards: [Wizard]
}

let crooks = CCat(name: "Crookshanks", age: 2)
let hermione = Wizard(name: "Hermione", cat: crooks)

let hedwig = CCat(name: "hedwig", age: 3)
let harry = Wizard(name: "Harry", cat: hedwig)

let gryffindor = Gryffindor(wizards: [harry, hermione])

print(gryffindor.value)

输出

name - kitten
age - 2
["age": 2, "name": "kitten"]
["name": "Hermione", "cat": ["age": 2, "name": "kitten"]]
["wizards": [["name": "Harry", "cat": ["age": 3, "name": "hedwig"]], ["name": "Hermione", "cat": ["age": 2, "name": "Crookshanks"]]]]