你尝试过使用 JSONSerialization.jsonObject(with:options:) 吗？
var jsonString = "{" +
"\"Language\": {" +
"\"Field\":[" +
"{" +
"\"Number\":\"976\"," +
"\"Name\":\"Test\"" +
"}," +
"{" +
"\"Number\":\"977\"," +
"\"Name\":\"Test\"" +
"}" +
"]" +
"}" +
"}"
var data = jsonString.data(using: .utf8)!
let json = try? JSONSerialization.jsonObject(with: data)
有时候，Swift会产生一些非常奇怪的语法。
if let number = json?["Language"]??["Field"]??[0]?["Number"] as? String {
print(number)
}
JSON对象层次结构中的所有内容最终都被包装为可选项（即AnyObject?）。 Array<T>下标返回非可选项T。对于这个被包装在可选项中的JSON，数组下标返回Optional<AnyObject>。然而，Dictionary<K，V>下标返回一个Optional<V>。对于这个JSON，下标返回非常奇怪的Optional<Optional<AnyObject>>（即AnyObject??）。
json是一个Optional<AnyObject>。json?["Language"]返回一个Optional<Optional<AnyObject>>。json?["Language"]??["Field"]返回一个Optional<Optional<AnyObject>>。json?["Language"]??["Field"]??[0]返回一个Optional<AnyObject>。json?["Language"]??["Field"]??[0]?["Number"]返回一个Optional<Optional<AnyObject>>。json?["Language"]??["Field"]??[0]?["Number"] as? String返回一个Optional<String>。Optional<String>然后被if let语法用来生成一个String。
最后注意：遍历字段数组的方式如下。
for field in json?["Language"]??["Field"] as? [AnyObject] ?? [] {
if let number = field["Number"] as? String {
print(number)
}
}
Swift 4 更新
Swift 4 让这一切变得更加容易处理。我们将再次从测试数据开始（使用"""可以让此过程更轻松愉悦）。
let data = """
{
"Language": {
"Field":[
{
"Number":"976",
"Name":"Test"
},
{
"Number":"977",
"Name":"Test"
}
]
}
}
""".data(using: .utf8)!
接下来，我们可以定义与您的JSON中使用的对象相关的类。
struct Object: Decodable {
let language: Language
enum CodingKeys: String, CodingKey { case language="Language" }
}
struct Language: Decodable {
let fields: [Field]
enum CodingKeys: String, CodingKey { case fields="Field" }
}
struct Field: Decodable {
let number: String
let name: String
enum CodingKeys: String, CodingKey { case number="Number"; case name="Name" }
}
CodingKeys 枚举用于将结构体属性映射到 JSON 对象成员字符串。这种映射是由 Decodable 自动完成的。
let object = try! JSONDecoder().decode(Object.self, from: data)
print(object.language.fields[0].name)
for field in object.language.fields {
print(field.number)
}
在Xcode 8和Swift 3中，id现在作为Any而不是AnyObject导入。
这意味着JSONSerialization.jsonObject(with: data)返回Any。因此，您必须将json data转换为特定类型，如[String：Any]。同样适用于json下面的下一个字段。
var jsonString = "{" +
"\"Language\": {" +
"\"Field\":[" +
"{" +
"\"Number\":\"976\"," +
"\"Name\":\"Test1\"" +
"}," +
"{" +
"\"Number\":\"977\"," +
"\"Name\":\"Test2\"" +
"}" +
"]" +
"}" +
"}"
var data = jsonString.data(using: .utf8)!
if let parsedData = try? JSONSerialization.jsonObject(with: data) as! [String:Any] {
let language = parsedData["Language"] as! [String:Any]
print(language)
let field = language["Field"] as! [[String:Any]]
let name = field[0]["Name"]!
print(name) // ==> Test1
}
在实践中，您可能希望在json中嵌套一些特定的字段。假设它是Field数组中第一个元素的Name字段。您可以使用这样的解包链来安全地访问该字段：
var data = jsonString.data(using: .utf8)!
if let json = try? JSONSerialization.jsonObject(with: data) as? [String:Any],
let language = json?["Language"] as? [String:Any],
let field = language["Field"] as? [[String:Any]],
let name = field[0]["Name"] as? String, field.count > 0 {
print(name) // ==> Test1
} else {
print("bad json - do some recovery")
}
您可能还想查看苹果公司的Swift博客 在Swift中使用JSON
let bundle = Bundle(for: type(of: self))
if let theURL = bundle.url(forResource: "response", withExtension: "json") {
do {
let data = try Data(contentsOf: theURL)
if let parsedData = try? JSONSerialization.jsonObject(with: data) as! [String:Any] {
grok(parsedData)
}
} catch {
print(error)
}
}
我使用您的JSON对象创建了一个mocky文件：
http://www.mocky.io/v2/5a280c282f0000f92c0635e6
这里是解析JSON的代码：
import UIKit
struct Item : Decodable {
// Properties must be the same name as specified in JSON , else it will return nil
var Number : String
var Name : String
}
struct Language : Decodable {
var Field : [Item]
}
struct Result : Decodable {
var Language : Language
}
class ViewController: UIViewController {
let url = "http://www.mocky.io/v2/5a280c282f0000f92c0635e6"
private func parseJSON() {
guard let url = URL(string: url) else { return }
let session = URLSession.shared.dataTask(with: url) { (data, response, error) in
guard let data = data else { return }
guard let result = try? JSONDecoder().decode(Result.self, from: data) else { return }
print("\n\nResult : \(result)")
}
session.resume()
}
override func viewDidLoad() {
super.viewDidLoad()
parseJSON()
}
}
Result : Result(Language: JSON_Parsing.Language(Field: [JSON_Parsing.Item(Number: "976", Name: "Test"), JSON_Parsing.Item(Number: "977", Name: "Test")]))
使用 Swift 4 简单地解析 JSON
let url = URL(string: "http://mobileappdevelop.co/TIPIT/webservice/get_my_groups?user_id=5")
URLSession.shared.dataTask(with:url!, completionHandler: {(data, response, error) in
guard let data = data, error == nil else { return }
do {
let json = try JSONSerialization.jsonObject(with: data, options: .allowFragments) as! [String:Any]
print(json)
let posts = json["Field"] as? [[String: Any]] ?? []
print(posts)
} catch let error as NSError {
print(error)
}
}).resume()
}
let count: Int? = json["Field"].array?.count
if let ct = count {
for index in 0...ct-1{
let number = json ["Field"][index]["number"].string
let name = json ["Field"][index]["name"].string
....
就像这样。
override func viewDidLoad() {
super.viewDidLoad()
let url=URL(string:"http://api.androidhive.info/contacts/")
do {
let allContactsData = try Data(contentsOf: url!)
let allContacts = try JSONSerialization.jsonObject(with: allContactsData, options: JSONSerialization.ReadingOptions.allowFragments) as! [String : AnyObject]
if let arrJSON = allContacts["contacts"] {
for index in 0...arrJSON.count-1 {
let aObject = arrJSON[index] as! [String : AnyObject]
names.append(aObject["name"] as! String)
contacts.append(aObject["email"] as! String)
}
}
print(names)
print(contacts)
self.tableView.reloadData()
}
catch {
}
}
dict = {
message = "Login successfully.";
status = 1;
"user_details" = (
{
dob = "1900-11-18";
email = "rizwan@gmail.com";
gender = male;
name = Rizwan;
nickname = Shaikh;
"profile_pic" = "1483434421.jpeg";
"social_id" = "<null>";
"user_id" = 2;
}
);
}
var dict2 = dict as! [String : Any]
print(dict);
let demoStr = dict2["message"] as! String
print(demoStr)
let demoArray = dict2["user_details"] as! [Any]
let demoDict = demoArray[0] as! [String:Any]
print(demoDict["dob"]!)
{...}开头和结尾。 - Jeffery Thomas