How to convert NSMutableArray to NSArray in swift?

How to convert NSMutableArray to NSArray in swift?

In Swift 3.0 there is new data type Array. Declare Array using let keyword then it would become NSArray And if declare using var keyword then it’s become NSMutableArray.

Can we use NSArray in Swift?

In Swift, the NSArray class conforms to the ArrayLiteralConvertible protocol, which allows it to be initialized with array literals. For more information about object literals in Swift, see Literal Expression in The Swift Programming Language (Swift 4.1).

How do I add elements to NSArray?

If you create an NSArray you won’t be able to add elements to it, since it’s immutable. You should try using NSMutableArray instead. Also, you inverted the order of alloc and init . alloc creates an instance and init initializes it.

Is NSMutableArray ordered?

Both are not ordered collections of objects, they are ordered collections of object references. NSMutableArray is capable of inserting and deleting elements at or near both the beginning and the end of the array quickly.

What is difference between Array and NSArray in Swift?

Array is a struct, therefore it is a value type in Swift. NSArray is an immutable Objective C class, therefore it is a reference type in Swift and it is bridged to Array . NSMutableArray is the mutable subclass of NSArray .

What is NSArray Objective-C?

NSArray is Objective-C’s general-purpose array type. It represents an ordered collection of objects. NSArray is immutable, so we cannot dynamically add or remove items. Its mutable counterpart, NSMutableArray, will be discussed in the second part of this tutorial.

What is filter in Swift?

The filter function loops over every item in a collection, and returns a collection containing only items that satisfy an include condition. It’s like applying an if-statement to a collection, and only keeping the values that pass the condition.