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

Posted by Andreas Parsley
Andreas Parsley
442 Points

How do you change the Key from "UK" to "ukCurrency"

I know one way of doing it but that would have me go back into the constant and change it...

I know there is a different way...

I really need some help

dictionaries.swift 
// Country Code     Currency
// or
// Key              Value
// Country          Currency
// US               Dollar
// UK               Pound
// JP               Yen

let currencies = [ "US": "Dollar", "UK": "Pound", "JP": "Yen"]

let ukCurrency = ["Pound"]

2 Answers

miguelcastro2
PLUS
miguelcastro2
Courses Plus Student 6,573 Points
miguelcastro2
miguelcastro2
Courses Plus Student 6,573 Points

Remember that dictionaries are key/value pairs. The first portion being the key and the portion following the ":" being the value:

let dictionary = [ "Key": "Value"]

// Change key from US to UnitedStates

// Before
let currencies = [ "US": "Dollar", "UK": "Pound", "JP": "Yen"]

// After
let currencies = [ "UnitedStates": "Dollar", "UK": "Pound", "JP": "Yen"]

// Change value from Dollar to $

// Before
let currencies = [ "US": "Dollar", "UK": "Pound", "JP": "Yen"]

// After
let currencies = [ "US": "$", "UK": "Pound", "JP": "Yen"]

Hope this helps.

Riley Spencer
Riley Spencer
1,753 Points
Riley Spencer
Riley Spencer
1,753 Points

let ukCurrency = ["UK']