Problem converting JSON to Array with Swift - arrays

Question

I try to convert a JSON to an Array but I face some issue and do not know how to sort it out.
I use Swift 5 and Xcode 12.2.
Here is the JSON from my PHP query:
[
{
Crewcode = AAA;
Phone = 5553216789;
Firstname = Philip;
Lastname = MILLER;
email = "pmiller#xxx.com";
},
{
Crewcode = BBB;
Phone = 5557861243;
Firstname = Andrew;
Lastname = DEAN;
email = "adean#xxx.com";
}
]
And here is my Swift code :
let url: URL = URL(string: "https://xxx.php")!
let defaultSession = Foundation.URLSession(configuration: URLSessionConfiguration.default)
let task = defaultSession.dataTask(with: url) { (data, response, error) in
if error != nil {
print("Failed to download data")
}
else {
print("Data downloaded")
do {
if let jsondata = (try? JSONSerialization.jsonObject(with: data!, options: [])) {
print(jsondata)
struct Crew: Decodable {
var Code: String
var Phone: String
var Firstname: String
var Lastname: String
var email: String
}
let decoder = JSONDecoder()
do {
let people = try decoder.decode([Crew].self, from: jsondata as! Data)
print(people)
}
catch {
print(error)
}
}
}
}
}
task.resume()
When I run my code I get the following error:
Could not cast value of type '__NSArrayI' (0x7fff86b930b0) to 'NSData' (0x7fff86b911e8).
2020-12-09 14:52:48.988468+0100 FTL[57659:3019805] Could not cast value of type '__NSArrayI' (0x7fff86b930b0) to 'NSData' (0x7fff86b911e8).
Could not cast value of type '__NSArrayI' (0x7fff86b930b0) to 'NSData' (0x7fff86b911e8).
Should you have any idea to get it right, I thank you in advance for your assistance on this !

Answer 1

You are deserializing the JSON twice by mixing up JSONSerialization and JSONDecoder.
Delete the first one
if let jsondata = (try? JSONSerialization.jsonObject(with: data!, options: [])) {
– By the way the JSON in the question is neither fish nor fowl, neither JSON nor an NS.. collection type dump –
and replace
let people = try decoder.decode([Crew].self, from: jsondata as! Data)
with
let people = try decoder.decode([Crew].self, from: data!)
and the struct member names must match the keys otherwise you have to add CodingKeys