Convert int to her string literal representation

NumberFormatter

Swift come with many formatter, we can found DateFormatter, LengthFormatter, EnergyFormatter.

Today I will introduce NumberFormatter, A formatter that converts between numeric values and their textual representations.

Code

import Foundation

let formatter = NumberFormatter()
formatter.string(from: 30)

Simple right? I’m kidding, it’s obviously not enough.

But here is the basic structure of the formatter

Tuning

Formatter come with many parameter.

For exemple if you want their textual representations of the number use the numberStyle property

let formatter = NumberFormatter()
formatter.numberStyle = .spellOut
formatter.string(from: 30)

// Output : Trentre

But you can get the currency value of this number

let formatter = NumberFormatter()
formatter.numberStyle = .currency
formatter.string(from: 30)
// Output : 30,00€

Fine Tuning

In the previous examples we got results in French. My native language.

But we can ask the format to use another locale

import Foundation

let formatter = NumberFormatter()
formatter.locale = Locale(identifier: "us_US")
formatter.numberStyle = .currency
formatter.string(from: 30)

// Output : $ 30.00

Bonus

Many people have trouble reading numbers: dyscalculia You can help with people with this simple trick

import Foundation

let formatter = NumberFormatter()
formatter.numberStyle = .currency
formatter.groupingSize = 3
formatter.string(from: 30000)

// Output: 30 000,00€

Simple!

And now ?

As you have seen this formatter brings a lot of logic in relation to the user’s locale, its monetary representation, but also its grammatical form.

Don’t code any more house stuff, use this formatter :)

Before leaving?

In a next article I will talk about another component provided by default about progress :)