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iOS Swift Collections and Control Flow Dictionaries in Swift Modifying a Dictionary

Emanuele Gorga
Emanuele Gorga
5,020 Points
Posted by Emanuele Gorga
Emanuele Gorga
5,020 Points

update dictionary

Hello guys, I have been trying in many different ways, trying to restart XCODE too but just doesn't want to work out. When I try to use updateValue in order to update a value in the dictionary (but because doesn't find anything it just add a new value), my Xcode is giving me an error:

var airportCodes: [String: String] = ["LGA": "La Guardia", "LHR": "Heathrow", "CDG": "Charles de Gaulle", "HKG": "Hong Kong International", "DXB": "Dubai International"]

airportCodes.updateValue("Dublin Airport", forKey: DUB)

Playground execution failed:

error: SwiftBasics.playground:72:52: error: use of unresolved identifier 'DUB' airportCodes.updateValue("Dublin Airport", forKey: DUB) ^~~

Do you know how to help me out? THANK YOU

1 Answer

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

You need the quotations around DUB because it is a string

var airportCodes: [String: String] = ["LGA": "La Guardia", "LHR": "Heathrow", "CDG": "Charles de Gaulle", "HKG": "Hong Kong International", "DXB": "Dubai International"]

airportCodes.updateValue("Dublin Airport", forKey: "DUB")
Emanuele Gorga
Emanuele Gorga
5,020 Points
Emanuele Gorga
Emanuele Gorga
5,020 Points

yeah perfect now it works :) thank you!