Parse JSON answer with Swift 3

Question

My JSON looks like this:

{"posts": [ { "id":"1","title":"title 1" }, { "id":"2","title":"title 2" }, { "id":"3","title":"title 3" }, { "id":"4","title":"title 4" }, { "id":"5","title":"title 5" } ], "text":"Some text", "result":1 } 

How can I parse that JSON with Swift 3?

I have it:

 let url = URL(string: "http://domain.com/file.php")! let request = URLRequest(url: url) let task = URLSession.shared.dataTask(with: request) { data, response, error in guard let data = data else { print("request failed \(error)") return } do { if let json = try JSONSerialization.jsonObject(with: data) as? [String: String], let result = json["result"] { // Parse JSON } } catch let parseError { print("parsing error: \(parseError)") let responseString = String(data: data, encoding: .utf8) print("raw response: \(responseString)") } } task.resume() } 

Answer 1

Use this to analyze data:

 let url = URL(string: "http://domain.com/file.php") 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] let posts = json["posts"] as? [[String: Any]] ?? [] print(posts) } catch let error as NSError { print(error) } }).resume() 

Use guard to check if you have data and that the error is empty.

Answer 2

In swift 3.0 for the GET method:

 var request = URLRequest(url: URL(string: "Your URL")!) request.httpMethod = "GET" let task = URLSession.shared.dataTask(with: request) { data, response, error in guard let data = data, error == nil else { // check for fundamental networking error print("error=\(String(describing: error))") return } if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 { // check for http errors print("statusCode should be 200, but is \(httpStatus.statusCode)") print("response = \(String(describing: response))") } let responseString = String(data: data, encoding: .utf8) print("responseString = \(String(describing: responseString))") } task.resume() 

In swift 3.0 for the POST method:

 var request = URLRequest(url: URL(string: "Your URL")!) request.httpMethod = "POST" let postString = "user_name=ABC" // Your parameter request.httpBody = postString.data(using: .utf8) let task = URLSession.shared.dataTask(with: request) { data, response, error in guard let data = data, error == nil else { // check for fundamental networking error print("error=\(String(describing: error))") return } if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 { // check for http errors print("statusCode should be 200, but is \(httpStatus.statusCode)") print("response = \(String(describing: response))") } let responseString = String(data: data, encoding: .utf8) print("responseString = \(String(describing: responseString))") } task.resume() 

Answer 3

Because your json test data structure must be "[String: AnyObject]". The posts value json key is an array type.

Answer 4

DISTANCE - DIFFICULT API =========================>

 class ViewController: UIViewController { var get_data = NSMutableData() var get_dest = NSArray() var org_add = NSArray() var row_arr = NSArray() var ele_arr = NSArray() var ele_dic = NSDictionary() var dist_dic = NSDictionary() var dur_dic = NSDictionary() override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view, typically from a nib. getmethod() } func getmethod() { let url_str = URL(string: "https://maps.googleapis.com/maps/api/distancematrix/json?units=imperial&departure_time=1408046331&origins=37.407585,-122.145287&destinations=37.482890,-122.150235") let url_req = URLRequest(url: url_str!) let task = URLSession.shared.dataTask(with: url_req) { (data, response, error) in if let my_data = data { print("my data is----->",my_data) do { self.get_data.append(my_data) let jsondata = try JSONSerialization.jsonObject(with: self.get_data as Data, options: [])as! NSDictionary print("json data is--->",jsondata) self.get_dest = jsondata.object(forKey: "destination_addresses")as! NSArray let get_dest1:String = self.get_dest.object(at: 0) as! String print("destination is--->",get_dest1) self.org_add = jsondata.object(forKey: "origin_addresses")as! NSArray let get_org:String = self.org_add.object(at: 0)as! String print("original address is--->",get_org) self.row_arr = jsondata.object(forKey: "rows")as! NSArray let row_dic = self.row_arr.object(at: 0)as! NSDictionary self.ele_arr = row_dic.object(forKey: "elements")as! NSArray self.ele_dic = self.ele_arr.object(at: 0)as! NSDictionary self.dist_dic = self.ele_dic.value(forKey: "distance")as! NSDictionary print("distance text is--->",self.dist_dic.object(forKey: "text")as! String) print("distance value is--->",self.dist_dic.object(forKey: "value")as! Int) // self.ele_dic = self.ele_arr.object(at: 1)as! NSDictionary self.dur_dic = self.ele_dic.value(forKey: "duration")as! NSDictionary print("duration text--->",self.dur_dic.value(forKey: "text")as! String) print("duration value--->",self.dur_dic.value(forKey: "value")as! Int) print("status---->",self.ele_dic.object(forKey: "status")as! String) } catch { print("error is--->",error.localizedDescription) } } };task.resume() }