difference between NSObject and Struct

Question

I want to know the difference between the NSObject and struct..Following example will explain both cases

In struct

struct UserDetails{
    var userName:String
    var userID:String
    var userAge:String
    func userDescription()->String{
        return "name " + userName + "age " + userAge
    }
}

In NSObject Class

class UserDetails: NSObject {
    var userName:String?
    var userID:String?
    var userAge:String?
    func userDescription()->String{
        return "name " + userName! + "age " + userAge!
    }
}

Can you anyone please tell me where I have to use NSObject class, where I have to use struct..?

Answer 1

1) Structs are passed by value, Class instances by reference 2) Classes can be subclassed, Structs can't.

Whether or not the Class is a subclass of NSObject is (mostly) irrelevant. You could equally have said:

class UserDetails {
    var userName:String?
    var userID:String?
    var userAge:String?
    func userDescription()->String{
        return "name " + userName! + "age " + userAge!
    }
}