Swift国内社区: SwiftMic
Swift版本: 4.0
通过 Codable 协议实现Swift对象与json字符串之间的互转。
简单数据结构
- 定义数据结构 User
struct User: Codable {
var name: String
var age: Int
}
- json字符串 -> User对象
let jsonStr = """
{
"name": "zzb",
"age": 18
}
"""
let jsonData = jsonStr.data(using: .utf8)!
let decoder = JSONDecoder()
do {
let userObj = try decoder.decode(User.self, from: jsonData)
print("userObj = \(userObj)")
} catch {
print("Decode error")
}
- User对象 -> json字符串
let user = User(name: "Cary", age: 20)
let encoder = JSONEncoder()
do {
let data = try encoder.encode(user)
let dataStr = String(data: data, encoding: .utf8)
print("dataStr = \(String(describing: dataStr))")
} catch {
print("Encode error")
}
复杂数据结构
- 定义数据结构 AdvancedUser
enum Gender: Int, Codable {
case male = 1
case female
}
class Location: Codable {
var lat: Double = 0.0
var lon: Double = 0.0
}
struct AdvancedUser: Codable {
var name: String
var age: Int
var gender: Gender
var location: Location
}
- json字符串 -> AdvancedUser对象
let jsonStr = """
{
"name": "zzb",
"age": 18,
"gender": 2,
"location": {
"lat": 99.9,
"lon": 87.5
}
}
"""
let jsonData = jsonStr.data(using: .utf8)!
let decoder = JSONDecoder()
do {
let userObj = try decoder.decode(AdvancedUser.self, from: jsonData)
print("userObj = \(userObj)")
} catch {
print("Decode error")
}
- AdvancedUser对象 -> json字符串
let location = Location()
location.lat = 99.9
location.lon = 87.5
let user = AdvancedUser(name: "Cary", age: 19, gender: .male, location: location)
let encoder = JSONEncoder()
do {
let data = try encoder.encode(user)
let dataStr = String(data: data, encoding: .utf8)
print("dataStr = \(String(describing: dataStr))")
} catch {
print("Encode error")
}
Demo源码
https://github.com/CaryZheng/iOSTutorials
