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What is the difference between NSDictionary and dictionary in Swift?

What is the difference between NSDictionary and dictionary in Swift?

4 Answers. Dictionary is a native Swift struct. NSDictionary is a Cocoa class. They are bridged to one another (within the usual limits), as the docs explain very clearly and fully.

How do I compare dictionaries in Swift?

Comparing Dictionaries If you wish to compare a dictionary with [String: String] type (or any value types). If the actual and expected dictionaries are different (for either the key or the value), the equality (==) will return false. If they are the same, the equality will return true.

What is the 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).

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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.

How do you define a dictionary in Objective-C?

Objective-C dictionary objects are created using the NSDictionary and NSMutableDictionary classes. NSDictionary based objects are immutable (in other words once they have been created and initialized their contents cannot be modified).

How do I create an NSDictionary in Objective-C?

Objective-C Language NSDictionary

  1. Create# NSDictionary *dict = [[NSDictionary alloc] initWithObjectsAndKeys:@”value1″, @”key1″, @”value2″, @”key2″, nil];
  2. NSDictionary to NSArray.
  3. NSDictionary to NSData.
  4. NSDictionary to JSON.
  5. Block Based Enumeration.
  6. Fast Enumeration.

How do I copy one dictionary to another in Swift?

In Swift, you have either value types (struct, enum, tuple, array, dict etc) or reference types (classes). If you need to copy a class object, then, you have to implement the methods copyWithZone in your class and then call copy on the object.

How do I sort a dictionary in Swift?

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A dictionary can be sorted by key or by value.

  1. Note: When sorting a dictionary, the returned type is an array of tuples. //Array.
  2. let arrayInc = array.sorted()
  3. //Dictionary.
  4. print(dict)
  5. let dictKeyInc = dict.sorted(by: <)
  6. print(dictKeyInc)
  7. let dictValInc = dict.sorted(by: { $0.value < $1.value })
  8. print(dictValInc)

How do I create an NSDictionary in Objective C?

How do you convert NSDictionary to NSMutableDictionary?

4 Answers. Use -mutableCopy . NSDictionary *d; NSMutableDictionary *m = [d mutableCopy]; Note that -mutableCopy returns id ( Any in Swift) so you will want to assign / cast to the right type.

Is NSDictionary ordered?

NSDictionary keys & values are not ordered.