JSONSerialization AnyObject SWIFT3 Conversion Issues

Question

I have converted to Swift 3 and I have received the following errors when assigning to AnyObject the JSONSerialization.jsonObject. Has anyone come across this issue and know the fix?

Answer 1

Since the last Swift 3 update most of the return types changed from AnyObject to Any and downcast is not allowed, so in such situation you are forced to use explicit cast. That means you should make a couple of guard statements or use optional chaining if let defining each necessary field. Consider using map, filter, reduce if possible to make your code more elegant. Example:

guard way:

guard let object = try JSONSerialization.jsonObject(with: data) as? [[String: Any]] else { return nil }
guard let field1 = object[0]["field1_token"] as? [Any] else { return nil }
//do your thing

if let way:

if let object = try JSONSerialization.jsonObject(with: data) as? [[String: Any]],
let field1 = object[0]["field1_token"] as? [Any] {
//do your thing
}

You may want to check Apple's article Working with JSON in Swift

Also you can use some of the json parsing/mapping libriaries like these:

SwiftyJSON

Gloss

Answer 2

Please replace let object : AnyObject with let object : Any.

Error showing because of wrong casting.