Check whether an object is an NSArray or NSDictionary

Question

As per subject, how can I check whether an object is an NSArray or NSDictionary?

Answer 1

Just in case anyone comes late to this party looking for a Swift equivalent, here you go. It's a lot more elegant than the Objective-C version, IMHO, because not only does it check the types, but it casts them to the desired type at the same time:

if let arrayVersion = obj as? NSArray {
    // arrayVersion is guaranteed to be a non-`nil` NSArray
} else if let dictionaryVersion = obj as? NSDictionary {
    // dictionaryVersion is guaranteed to be a non-`nil` NSDictionary
} else {
    // it's neither
}