Store JSON data as a variable - ios

Question

I'm trying to figure out how to store JSON data into a variable for later use. How do I store it, and is it possible to use the variable in another view controller, or do I have to do another request to fetch the data?
This is my code:
#IBAction func signinTapped(_ sender: UIButton) {
guard let url = URL(string: "http://XXXXXX/TestReqIOS.php") else {
return
}
let email = txtEmail.text!
let password = txtPassword.text!
let data : Data = "loginSubmit=1&email=\(email)&password=\(password)&grant_type=password".data(using: .utf8)!
var request : URLRequest = URLRequest(url: url)
request.httpMethod = "POST"
request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField:"Content-Type");
request.setValue(NSLocalizedString("lang", comment: ""), forHTTPHeaderField:"Accept-Language");
request.httpBody = data
print("Calling API")
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
// vs let session = URLSession.shared
// make the request
let task = session.dataTask(with: request, completionHandler: {
(data, response, error) in
if let error = error {
print("error")
}
else if let response = response {
print("response")
}
else if let data = data {
print(data)
}
DispatchQueue.main.async { // Correct
guard let responseData = data else {
print("Error: did not receive data")
return
}
print(String(data: responseData, encoding: String.Encoding.utf8) ?? "")
}
})
task.resume()
}
Which will return:
{
"id": "7",
"first_name": "John",
"last_name": "Doe",
"email": "JohnDoe#text.com",
"created": "2019-03-11",
"modified": "2019-03-10",
}

Answer 1

It would be better to use a struct, such as in your case:
struct Data: Codable {
let id: Int
let first_name: String
let last_name: String
let email: String
let created: Date
let modified: Date
}
Then you create a variable of that struct where you will store it:
var dataVariable = [Data]()
Then you can do your URL call like:
func getData(arr: Bool, completion: #escaping (Bool) -> ()) {
let urlJSON = "URL"
guard let url = URL(string: urlJSON) else { return }
URLSession.shared.dataTask(with: url) { (data, response, err) in
guard let data = data else { return }
do {
let getData = try JSONDecoder().decode([Data].self, from: data)
self.dataVariable = getData
} catch let jsonErr {
print("error serializing json: \(jsonErr)")
}
completion(arr)
}.resume()
}
Then you can access all of this from the dataVariable var. IF you do this in a Manager class you can access it from any ViewController.
To access:
let firstNameString = dataVariable[0].first_name
If there are not multiple trees of the same, then just make sure its:
let getData = try JSONDecoder().decode(Data.self, from: data)
Edit:
In your case put the above here:
let task = session.dataTask(with: request, completionHandler: {
(data, response, error) in
if let error = error {
print("error")
}
else if let response = response {
print("response")
}
else if let data = data {
let getData = try JSONDecoder().decode([Data].self, from: data)
self.dataVariable = getData // <- Just decode here
print(data)
}
DispatchQueue.main.async { // Correct
guard let responseData = data else {
print("Error: did not receive data")
return
}
print(String(data: responseData, encoding: String.Encoding.utf8) ?? "")
}
})
task.resume()