How to save the JSON data to UserDefault in Swift? [duplicate] - ios

Question

This question already has answers here:
saving swifty json array to user defaults
(4 answers)
Closed 2 years ago.
I made a post request using Alamofire. This is my code to fetch data from server using an endpoint:
Alamofire.request("http://192.168.80.21:3204/api/auth/signin", method: .post, parameters: parameters,encoding: JSONEncoding.default, headers: nil).responseJSON {
response in
switch response.result {
case .success(let value):
let json = JSON(value)
print(json)
break
case .failure(let error):
print("Error :- \(error)")
}
}
}
And this is the data i get from the server:
{
"accessToken" : "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpZCI6NTIsInJvbGUiOjEsImlhdCI6MTYwMzg2ODUxNCwiZXhwIjoxNjAzOTU0OTE0fQ.y68w8XQfqFZDVgaxiuFuVCOqaI5e5vZ-SfoDB_Ctxro",
"role" : "admin",
"auth" : true
}
I want to save the response to UserDefault for further use. Help me to save the data to Userdefault and retrieve and print data.

Answer 1

Create a model, a struct conforming to Codable
struct Auth: Codable {
let accessToken, role: String
let auth: Bool
}
and extend UserDefaults
extension UserDefaults {
func auth(forKey defaultName: String) -> Auth? {
guard let data = data(forKey: defaultName) else { return nil }
do {
return try JSONDecoder().decode(Auth.self, from: data)
} catch { print(error); return nil }
}
func set(_ value: Auth, forKey defaultName: String) {
let data = try? JSONEncoder().encode(value)
set(data, forKey: defaultName)
}
}
Now you can use auth(forKey:) and set(_:forKey:) to read and write an Auth instance directly.
Drop SwiftyJSON and change the Alamofire part to decode the JSON into the struct with JSONDecoder
Alamofire.request("http://192.168.80.21:3204/api/auth/signin", method: .post, parameters: parameters).responseData {
response in
switch response.result {
case .success(let data):
do {
let auth = try JSONDecoder().decode(Auth.self, from: data)
print(auth)
UserDefaults.standard.set(auth, forKey: "Auth")
} catch { print(error) }
case .failure(let error):
print("Error :- \(error)")
}
}
To read the instance write
let auth = UserDefaults.standard.auth(forKey: "Auth")

Answer 2

accessToken
func setInDefault<T: Codable>(key: String, type: T.Type, data: T?) {
guard let data = data else {
return
}
do {
let encoder = JSONEncoder()
let encodeData = try encoder.encode(data)
let dict:[String:Any] = try JSONSerialization.jsonObject(with: encodeData, options: .allowFragments) as! [String : Any]
let data = NSKeyedArchiver.archivedData(withRootObject: dict)
//set user data in defaults
UserDefaults.standard.set(data, forKey: key)
UserDefaults.standard.synchronize()
} catch {
print(error)
//handle error
}
}
func getFromDefault<T: Codable>(key: String, type: T.Type) -> T? {
let archieved = UserDefaults.standard.value(forKey: key)
let dict = NSKeyedUnarchiver.unarchiveObject(with: archieved as? Data ?? Data())
let decoder = JSONDecoder()
do {
if let dic = dict {
let data = try JSONSerialization.data(withJSONObject: dic, options: .prettyPrinted)
return try decoder.decode(type, from: data)
}
} catch {
print(error)
//handle error
}
return nil
}
You can use the above func. like below.
setInDefault(key: "userData", type: AuthUser.self, data: data)
Here,
Param: data is a generic parameter of type T. So here you need to pass the response data you get from server. (It should be Codable class type)
Param: AuthUser is
struct AuthUser : Codable {
let accessToken : String?
let role: String?
let auth: Bool?
enum CodingKeys: String, CodingKey {
case accessToken = "accessToken"
case role = "role"
case auth = "auth"
}
init(from decoder: Decoder) throws {
let values = try decoder.container(keyedBy: CodingKeys.self)
accessToken = try values.decodeIfPresent(String.self, forKey: .accessToken)
role = try values.decodeIfPresent(String.self, forKey: .role)
auth = try values.decodeIfPresent(Bool.self, forKey: .auth)
}
}
To get data:
let data = getFromDefault(key: "userData", type: AuthUser.self)
print(data)

Answer 3

If you use global variable. You can use save method according to your purpose which is written below :
let objects = [yourObjectClass]()
func save() {
let jsonEncoder = JSONEncoder()
if let savedData = try? jsonEncoder.encode(objects) {
let defaults = UserDefaults.standard
defaults.set(savedData, forKey: "objects")
} else {
print("Failed to save objects.")
}
}
}

Answer 4

You can save JSON Model data in Userdefaults Using below function code
func saveData(data: yourModelData){
var userDefaults = UserDefaults.standard
let encodedData: Data = NSKeyedArchiver.archivedData(withRootObject: yourModelData)
userDefaults.set(encodedData, forKey: "yourKey")
userDefaults.synchronize()
}
and retrive Data from Userdefaults use this function
func getData() -> yourModelData {
var userDefaults = UserDefaults.standard
let decoded = userDefaults.data(forKey: "yourKey")
let decodedData = NSKeyedUnarchiver.unarchiveObject(with: decoded) as! [yourModelData]
return decodedData
}