How to use enum in Swift

Swift Enumerations

7 Mar 2023 . 2 min read       @gurjitpt


Enumerations defines a type for group of related values.


Enumerations (enum) enables you to write code in a type safe way. Enum is very useful while defining common type of values. You don't have to provide value while defining enum.


Syntax

You can declare enumerations with enum keyword.

enum SomeEnumerations {
  
}


Here is a basic example of defining enumeration. You can use case keyword to define new enumeration cases.

enum Direction {
  case north
  case south
  case east
  case west
}


You can also define cases in single line rather than multiple lines. For example,

enum DaysOfWeek {
  case sunday, monday, tuesday, wednesday, thursday, friday, saturday
}


You can assign enum value to new variable in following way.

var day = DaysOfWeek.sunday


Matching enum values using switch statement

You can match value of enum using switch statement in following way.

var direction = Direction.west

switch direction {
  case .east:
    print("Marked with E")
  case .west:
    print("Marked with W")
  case .north:
    print("Marked with N")
  case .south:
    print("Marked with S")
  default:
    print("Direction not found")
}


Iterating over enumeration cases

You can perform iteration over enum cases using CaseIterable. You have to write CaseIterable after the enum name. For example,

enum Season: CaseIterable {
  case summer, winter, spring, autumn
} 

let typeofSeasons = Season.allcases.count
print("There are \(typeofSeasons) type of seasons.")


You can iterate over all cases of enum using for-in loop.

for season in Season.allCases {
  print(season)
}



Don’t hesitate to contact me if you have any questions or queries. Follow me on twitter @gurjitpt for any updates.

Thanks!


Share this article


Generic placeholder image

WRITTEN BY

Gurjit Singh

I’m Computer Science graduate and an iOS Engineer who writes about Swift and iOS development. Follow me on twitter @gurjitpt for more updates.


Next Posts

How to cache data in Swift using NSCache

When we develop apps for iOS, we need to perform heavy tasks such as loading images from the network, loading files, etc. It’s a very time-consuming ...

Apr 7, 2023 . 2 min read     Swift NSCache

Read More »

Optional unwrapping syntax in Swift 5.7 Empty space for void

Optional unwrapping is one of the most used patterns in iOS development. Swift 5.7 introduces new features included a new way to unwrap optional values...

Jun 14, 2022 . 2 min read     Optional unwrapping

Read More »

Property observers in Swift Empty space for void

It's a common pattern or technique in various programming languages when we want to perform some action when a value is changed. Property ...

May 24, 2021 . 2 min read     Property Observers

Read More »