gerrior / ios-module-project-swift-fundamentals-iii-playground

Swift Fundamentals III Module Project

Please fork and clone this repository

The goal of today's module project is to create a Currency Conversion playground that can convert from US dollars (USD) to Canadian dollars (CAD) and Mexican Pesos (MXN).

Get the currency conversion value from Google:

On August 7th, 2019 they were:

$1 USD to $1.33 CAD
$1 USD to $19.70 MXN

Add the Conversion Logic

Create a new playground in this repository called "CurrencyConverter"

1. Create a currency type enum below the import statements.

   enum Currency {
       case cad
       case mxn
   }

2. Create a constant called usToCad and set its value to the current conversion value (googling usd to cad should give you the value). Do the same for a new constant called usToMxn.

3. Create a property named currency of type Currency. This will store the current currency type we'll be converting to. Set an initial value of .cad.

4. Create a helper method to calculate the currency based on the Currency using the method signature:

   func convert(_ dollars: Double) -> Double {
   
   }

5. In the above method:

   • Check the value of currency to see whether you should convert to CAD or MXN
   • Perform the conversion with the dollars passed into this method
   • Return the converted value

6. Create a function called convert(amountString: String) -> String? In it, do the following:

   • create a constant called amount. Its value should be the amountString that is initialized into a Double
   • use a guard let to unwrap the new amount constant.
   • convert the dollar amount to the expected currency (hint, you'll want to call the convert method you created in step 4

7. Test your code by calling convert(amountString with some values. Change your currency to both .cad and .mxn (by manually changing the value of your currency variable above) to make sure the conversion works for both currencies.

Go Further (Optional)

1. Customize the output using a NumberFormatter

   var currencyFormatter: NumberFormatter = {
       let formatter = NumberFormatter()
       formatter.numberStyle = .currency
       return formatter
   }()

2. Use the string(from:) method to convert from a number to a String for display