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iOS Swift Basics (retired) Collections What is a Dictionary?

Posted by Ling Cheng
Ling Cheng
3,168 Points

how can I Assign the value for key "UK" to a constant named ukCurrency when it is constant?

I tried on Xcode, if var currencies works, but now is a constant, how can I work this out ? thanks!

dictionaries.swift 
let currencies = ["US": "Dollar", "UK": "Pound", "JP": "Yen"]
currencies.removeValueForKey ("UK")
let ukCurrency = currencies.removeValueForKey ("UK")

3 Answers

William Li
William Li
Courses Plus Student 26,868 Points

Hi, Ling.

No, you don't need to remove anything from the dictionary. What part 2 asks you to do are couple things

  1. retrieve the value of "UK" key from currencies dictionary.
  2. assign that value to a new constant named ukCurrency 
let currencies = ["US": "Dollar", "UK": "Pound", "JP": "Yen"]
let ukCurrency = currencies["UK"]
Holger Liesegang
Holger Liesegang
50,595 Points
Holger Liesegang
Holger Liesegang
50,595 Points

Hi Ling,

you get the value for the key "UK" in the dictionary currencies like this: currencies["UK"]

let currencies = ["US": "Dollar", "UK": "Pound", "JP": "Yen"]
let ukCurrency = currencies["UK"]
Ling Cheng
Ling Cheng
3,168 Points
Ling Cheng
Ling Cheng
3,168 Points

Oh,...thanks both!! I was thinking too much....need to study more, thanks !