Issue in Parsing JSON object from CoreData - ios

Question

I converted a JSON object to string and stored it to CoreData. But how to parse the individual elements and get each of the elements after retrieving the JSON object that I'm not able to figure out....
This is how I'm getting the json object:
let mobileNumber = mobileNumberTextfield.text
let firstName = firstNameTextField.text
let jsonObject: [String: [String:Any]] = [
"user1": [
"mobile_number": mobileNumber,
"first_Name": firstName,
]
]
I'm printing JSON string like so...
if let data = try? JSONSerialization.data(withJSONObject: jsonObject, options: .prettyPrinted),
let str = String(data: data, encoding: .utf8) {
print(str)
}
printing str gives:
{
"user1" : {
"mobile_number" : "567567567",
"first_Name" : "iopiopi",
}
}
I'm storing it as it is to coredata and so when I retrive it I get it back in the very same format as above. But how can I retrieve the individual elements for later use that I can't figure out.
If I fetch it something like so...
for result in newProductDetails {
if let prodID = result.value(forKey: "address") as? String {
print(prodID)
}
}
and do a for (key, value) in addDetails.enumerated() & print value, it give this..
data: {
address = "{
\n \"user1\" : {
\n \"mobile_number\" : \"1236594525\",
\n \"first_Name\" : \"ghj\"
\n
}
\n
}";
})
But how can I extract individual values of mobile_number & first_Namefrom it ...?

Answer 1

You are storing the data (NSData obtained from the string encoding the JSON) and getting back that same data from CoreData. That means you have to parse the JSON in that NSData instance again. The round trip to JSON/NSData and back makes little sense. You probably just want to create an User entity and store the mobile number and first name into CoreData directly.

Answer 2

Convert Json string to Dictionary:
func convertToDictionary(text: String) -> [String: Any]? {
if let data = text.data(using: .utf8) {
do {
return try JSONSerialization.jsonObject(with: data, options: []) as? [String: Any]
} catch {
print(error.localizedDescription)
}
}
return nil
}
let str = "{\"name\":\"James\"}"
let dict = convertToDictionary(text: str)
You should save like this in CoreData:
if let reposArray: AnyObject = json["user1"] as? NSDictionary {
self.mbleNo = reposArray["mobile_number"] as? String
let appDelegate = UIApplication.shared.delegate as! AppDelegate
if #available(iOS 10.0, *) {
let managedObjectContext = appDelegate.persistentContainer.viewContext
let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "Fields")
let entityDescription = NSEntityDescription.entity(forEntityName: "Fields", in:managedObjectContext)
let titleInfo = NSManagedObject(entity: entityDescription!, insertInto: managedObjectContext) as? Fields
titleInfo?.setValue(self.mbleNo, forKey: "mobile_number")
do {
try titleInfo?.managedObjectContext?.save()
}
catch {
print(error)
}
}
}