Removing pairs

Bob — er, sorry — Bobby, still doesn’t feel safe, and he wants you to remove all information about his whereabouts:

bobData.removeValue(forKey: "state")

This method will remove the key state and its associated value from the dictionary. As you might expect, there’s a shorter way to do this using subscripting:

bobData["city"] = nil

Assigning nil as a key’s associated value removes the pair from the dictionary.

Note: If you are using a dictionary that has values that are optional types, dictionary[key] = nil still removes the key completely. If you want keep the key and set the value to nil you must use the updateValue method.