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iOS Swift Enums and Structs Structs and their Methods Struct Methods

Tim Hancock
Tim Hancock
3,254 Points

How do I call a method on a variable?

I'm struggling with the last part of this code challenge. How do I call a function in a struct and assign it to a new variable?

struct Expense {
    var description: String
    var amount: Double = 0.0

    init (description: String) {
        self.description = description

    func calculateTaxes(percentage: Double) -> Double{
    return self.amount * (percentage/100)}

    var item = Expense(description: "Booger")
item.amount = 100

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points


What you want to do is call the function, and the function will return a value. This value can then be assign to a variable.

// If you have an instance of the struct

var item = Expense(description: "Booger")

// then you can call the function 

var newVariable = item.calculateTaxes(7.0)

Hope this small explanation helps you