Swift equivalent to `[NSDictionary initWithObjects: forKeys:]`

by

As of Swift 4 you can create a dictionary directly from a
sequence of key/value pairs:

let keys = ["one", "two", "three"]
let values = [1, 2, 3]

let dict = Dictionary(uniqueKeysWithValues: zip(keys, values))

print(dict) // ["one": 1, "three": 3, "two": 2]

This assumes that all keys are different, otherwise it will abort
with a runtime exception.

If the keys are not guaranteed to be distinct then you can do

let keys = ["one", "two", "one"]
let values = [1, 2, 3]

let dict = Dictionary(zip(keys, values), uniquingKeysWith: { $1 })

print(dict) // ["one": 3, "two": 2]

The second argument is a closure which determines which value “wins”
in the case of duplicate keys.

More Related Contents:

  1. Swift – Stored values order is completely changed in Dictionary
  2. How to Read Plist without using NSDictionary in Swift?
  3. How do I make an HTTP request in Swift?
  4. How to use NSJSONSerialization
  5. NSDictionary with ordered keys
  6. Passing data between view controllers
  7. Save images in NSUserDefaults?
  8. UIImageView – How to get the file name of the image assigned?
  9. How to share an image on Instagram in iOS?
  10. MKMapView: Instead of Annotation Pin, a custom view
  11. Detect current device with UI_USER_INTERFACE_IDIOM() in Swift
  12. Best way to sort an NSArray of NSDictionary objects?
  13. How to modify SWIFT_MODULE_NAME?
  14. ViewDidAppear is not called when opening app from background
  15. Array from dictionary keys in swift
  16. Add bottom border line to UI TextField view in SwiftUI / Swift / Objective-C / Xamarin
  17. Positioning UITabBar at the top
  18. UITableViewCell with dynamic height iOS
  19. What is the difference between Modal and Push segue in Storyboards?
  20. NSDate – Convert Date to GMT
  21. [NSObject : AnyObject]?’ does not have a member named ‘subscript’ error in Xcode 6 beta 6
  22. How to add a button to the MKPointAnnotation?
  23. Swift performSelector:withObject:afterDelay: is unavailable [duplicate]
  24. When to use takeUnretainedValue() or takeRetainedValue() to retrieve Unmanaged Objects in Swift?
  25. Xcode 9 – failed to emit precompiled header [duplicate]
  26. Why can’t I call the default super.init() on UIViewController in Swift?
  27. UIView’s border color in Interface builder doesn’t work?
  28. Setting up UIScrollView to swipe between 3 view controllers
  29. AutoLayout views make app crash on popViewController
  30. UIDevice currentDevice model possible values

Leave a Comment