How to retrieve JSON data from webpage - ios

Question

My webpage displays a constructive data in a single line, specifically to let my app retrieve it.
JSON
[{"long":"1234..45","lat":"345.12"}]
This information is in a page, click here to see: http://www.gogrex.com/Sandbox/startloc.json
How do I retrieve it into my app as a JSON? I have looked thru many examples but still cannot solve it.

Answer 1

Swift 3.x
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
// create your get url
let getURL = URL(string: "http://www.gogrex.com/Sandbox/startloc.json")!
// use URLSession to get the data from your website
URLSession.shared.dataTask(with: getURL) { (data, response, error) in
guard let data = data, error == nil else {
print(error?.localizedDescription ?? "nil")
return
}
// you need to serialize your data using JSONSerialization jsonObject(with:options)
do {
if let jsonArray = try JSONSerialization.jsonObject(with: data, options: .allowFragments) as? [Any],
let jsonDict = jsonArray.first as? [String: Any] {
let latString = jsonDict["lat"] as? String
let longString = jsonDict["long"] as? String
print("latitude = ", latString ?? "nil") // 345.12
print("longitude = ", longString ?? "nil") // 1234..45 ( you need to fix this value)
print(Double(latString ?? "nil") ?? "nil") // Optional(345.12)
print(Double(longString ?? "nil") ?? "nil") // nil
}
} catch let error as NSError {
print(error.localizedDescription)
}
}.resume()
}
}
Swift 2.3
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let getURL = NSURL(string: "http://www.gogrex.com/Sandbox/startloc.json")!
NSURLSession.sharedSession().dataTaskWithURL(getURL) { (data, response, error) in
guard let data = data where error == nil else {
print(error?.localizedDescription)
return
}
do {
if let jsonArray = try NSJSONSerialization.JSONObjectWithData(data, options: .AllowFragments) as? [AnyObject],
let jsonDict = jsonArray.first as? [String:AnyObject] {
let latString = jsonDict["lat"] as? String ?? ""
let longString = jsonDict["long"] as? String ?? ""
print("latitude = ", latString) // 345.12
print("longitude = ", longString) // 1234..45 ( you need to fix this value)
print(Double(latString)) // Optional(345.12)
print(Double(longString)) // nil
}
} catch let error as NSError {
print(error.localizedDescription)
}
}.resume()
}
}
Don't forget to edit your info.plist to add your web domain