I've set some user defaults using let userDefaults = UserDefaults.standard, and when I'm retrieving them, I can use any of these:
jobTextField.text = userDefaults.object(forKey: "job") as? String
OR I can use
jobTextField.text = userDefaults.value(forKey: "job") as? String
in what case this will has a difference? It'd be great to know when I can NOT use one of them.
Thanks a lot :)
value(forKey:) is from key-value coding, and not a direct method of UserDefaults.
Never use value(forKey:) on UserDefaults or Dictionary or any other class unless you have a clearly understood need to use key-value coding to get the desired result.
When you don't have such a need, use the standard access methods provided by the class in question (such as UserDefaults object(forKey:).
value(forKey:) in the example for using key paths with Swift 4 and UserDefaults. Why is that? And what would be the reasons for using it over object(forKey:)?value(forKey:)The two are completely different. The value(forKey:) is not a UserDefaults-only method. It is enabled by the NSKeyValueCoding, which, According to Apple's Documentation:
NSKeyValueCodingis an informal protocol that objects adopt to provide indirect access to their properties. When an object is key-value coding compliant, its properties are addressable via string parameters through a concise, uniform messaging interface.
It happens that UserDefaults is NSKeyValueCoding compliant, so people have started (not necessarily in the correct way) using it for accessing UserDefaults.
object(forKey:)This is the correct way to access UserDefaults's properties. Unless you do not have a very good reason to use value(forKey:), always use object(forKey:), or the other valid methods of UserDefaults (i.e. string(forKey:)).
Hope this clears things up!
