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Start your free trialSebastian Eguez
8,248 PointsWhat is the difference between updateValue and...
// Dictionaries
/*
Airport Code (Key) Airport Name (Value)
LGA La Guardia
LHR Heathrow
CDG Charles de Gaulle
HKG Hong Kong International
DXB Dubai International
*/
// ["LGA": "La Guardia", "LHR": "Heathrow", "CDG": "Charles de Gaulle", "HKG": "Hong Kong International", "DXB": "Dubai International" // You can also write this like BELOW
var airportCodes: [String: String] =
[
"LGA": "La Guardia",
"LHR": "Heathrow",
"CDG": "Charles de Gaulle",
"HKG": "Hong Kong International",
"DXB": "Dubai International"
]
let currentWeather = ["Temperature": 75.0] // Press the option button and hover over currentWeather
// Reading from a dictionary
airportCodes["LGA"]
airportCodes["HKG"]
// Inserting Key Value Pairs
airportCodes["SYD"] = "Sydney Airport" // airportCodes needs to be a var to insert a key value pair
airportCodes["LGA"] = "La Guardia International Airport"
airportCodes["LGA"]
airportCodes.updateValue("La Guardia Airport", forKey: "LGA")
What is the difference between changing "LGA": "La Guardia" using
airportCodes["LGA"] = "La Guardia International Airport"
and
airportCodes.updateValue("La Guardia Airport", forKey: "LGA")
?
Why and when should you use one or the other?
Thanks.
1 Answer
Matt Skelton
4,548 PointsHey Sebastian,
I started typing an explanation for the advantages of using each, and then I stumbled upon this in the Apple documentation.
Take a look at the section under "Accessing and Modifying a Dictionary", it covers your question with examples and describes it much better than I could!
Sebastian Eguez
8,248 PointsSebastian Eguez
8,248 PointsThanks.
mrtroy
8,069 Pointsmrtroy
8,069 PointsThe Apple documentation did a good job of explaining how to use the Dictionary but I am still wondering if the method way is better then an assignment. It does have more options but does it conserve CPU time or space?