目前主流的Json转Mode框架:
SwiftyJSON Github 上 Star 最多的 Swift JSON 解析框架
ObjectMapper 面向协议的 Swift JSON 解析框架
HandyJSON阿里推出的一个用于 Swift 语言中的 JSON 序列化/反序列化库。
KakaJSON mj新写的一个转模型工具
JSONDecoder Apple 官方推出的基于
Codable的 JSON 解析类
这里主要总结下JSONDecoder的使用,毕竟亲儿子的前途要更光明些
官方介绍
下面的示例展示了如何从JSON对象解码一个GroceryProduct类型实例。该类型采用Codable，因此它可以使用JSONDecoder实例进行解码
// 定义模型名称
struct GroceryProduct: Codable {
var name: String
var points: Int
var description: String?
}
let json = """
{
"name": "Durian",
"points": 600,
"description": "A fruit with a distinctive scent."
}
""".data(using: .utf8)!
// 对data数据进行解析
let decoder = JSONDecoder()
let product = try? decoder.decode(GroceryProduct.self, from: json)
// 读取model中数据
print(product?.description ?? "nil")
func decode<T>(_ type: T.Type, from data: Data) throws -> T where T : Decodable
typejson解析之的类型data要解析的数据
复杂类型数据结构使用
当出现多层嵌套时
let json2 = """
{
"id": 1001,
"name": "Durian",
"points": 600,
"parameters": {
"size": "80*80",
"area": "Thailand",
"quality": "bad"
},
"description": "A fruit with a distinctive scent."
}
""".data(using: .utf8)!
这时候我们的模型类做相应的struct处理
如果key的名字想自定义,可通过CodingKey来实现转换
这里假设quality为有限类型时,可通过枚举来显示,更加直观
struct GroceryProduct: Codable {
var ID: Int
var name: String
var points: Int?
var description: String?
var parameters: Parameters?
enum CodingKeys: String, CodingKey {
case ID = "id"
case name
case points
case description
case parameters
}
struct Parameters: Codable {
var size: String?
var area: String?
var quality: Quality?
}
enum Quality: String, Codable {
case good, caporal, bad
}
}
解析和调用
do {
decoder.keyDecodingStrategy = .convertFromSnakeCase
let product2 = try decoder.decode(GroceryProduct.self, from: json2)
print(product2.parameters?.quality ?? "unknown")
} catch let error {
print(error)
}
列表数据
模拟请求列表数据
{
"code": 10000,
"msg": "请求成功",
"datas" : [
{
"id": 1001,
"name": "Durian",
"points": 600,
"parameters": {
"size": "80*80",
"area": "Thailand",
"quality": "bad"
},
"description": "A fruit with a distinctive scent."
},
{
"id": 1002,
"name": "Apple",
"points": 600,
"parameters": {
"size": "80*80",
"area": "China",
"quality": "good"
},
"description": "A round fruit with shiny red or green skin and firm white flesh."
},
{
"id": 1003,
"name": "Arange",
"points": 600,
"parameters": {
"size": "80*80",
"area": "China",
"quality": "caporal"
},
"description": "A round citrus fruit with thick reddish-yellow skin and a lot of sweet juice."
},
{
"id": 1004,
"name": "Banana",
"points": 600,
"parameters": {
"size": "80*80",
"area": "Malaysia",
"quality": "good"
},
"description": "A long curved fruit with a thick yellow skin and soft flesh, that grows on trees in hot countries."
}
]
}
创建model类
struct ProductListModel: Codable {
var code: Int
var msg: String
var datas: [GroceryProduct]
}
请求数据源并解析
guard let urlPath = Bundle.main.path(forResource: "ProductList", ofType: "json") else { return }
do {
let data = try Data(contentsOf: URL(fileURLWithPath: urlPath))
let jsonData: Any = try JSONSerialization.jsonObject(with: data, options: JSONSerialization.ReadingOptions.mutableContainers)
print("present = ", jsonData)
let product3 = try decoder.decode(ProductListModel.self, from: data)
print(product3.datas[2].ID)
} catch let error {
print(error)
}
注意事项
- 数据类型一定要匹配,否则解析失败
