How do you get the key in NSDictionary?

How do you get the key in NSDictionary?

3 Answers

  1. To get the first key only is NSString *firstKey = [dict allKeys][0]; – Mazen Kasser.
  2. @MazenKasser firstObject is a safer solution – in case if the dictionary doesn’t have any keys the app won’t crash: dict. allKeys.
  3. the order of keys returned by allKeys is undefined…

What is NSDictionary in Swift?

An object representing a static collection of key-value pairs, for use instead of a Dictionary constant in cases that require reference semantics.

What is the key difference between NSDictionary and NSMutableDictionary?

Main Difference is: NSMutableDictionary is derived from NSDictionary, it has all the methods of NSDictionary. NSMutableDictionary is mutable( can be modified) but NSDictionary is immutable (can not be modified).

Is NSDictionary ordered?

NSDictionary keys & values are not ordered.

Is NSDictionary thread safe?

NSMutableDictionary isn’t designed to be thread-safe data structure, and simply marking the property as atomic , doesn’t ensure that the underlying data operations are actually performed atomically (in a safe manner).

What is NSDictionary in Objective C?

In this tutorial, we will be covering various functions available in NSDictionary. NSDictionary help us in creating static dictionary. Modern Objective C Dictionary notations. There is modern Objective C syntax that makes it easier for us to create and retrieve objects. Xcode actually changes to required format in build time.

What is NSDictionary in Xcode?

NSDictionary help us in creating static dictionary. Modern Objective C Dictionary notations. There is modern Objective C syntax that makes it easier for us to create and retrieve objects. Xcode actually changes to required format in build time.

How to initialize a newly allocated Dictionary?

Initializes a newly allocated dictionary using the keys and values found at a given URL. Initializes a newly allocated dictionary by placing in it the keys and values contained in another given dictionary. Initializes a newly allocated dictionary using the objects contained in another given dictionary.

What is initialize dictionary in C++?

Initializes a newly allocated dictionary by placing in it the keys and values contained in another given dictionary. Initializes a newly allocated dictionary using the objects contained in another given dictionary. Initializes a newly allocated dictionary with entries constructed from the contents of the objects and keys arrays.

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