Swift – Arrays Properties
An array is one of the most commonly used data types because of the benefits it provides in writing programs more efficiently. Just like other programming languages, in the Swift language, also array is a collection of similar data types. It stores data in an order list. When you assign an array to a variable, then your variable is mutable which means you can remove, add, or modify the elements present in the array. And when you assign an array to a constant, then your array will be immutable which means you cannot modify and change the size of the array. Before understanding the properties of the array first of all we understand how to create array:
var myarray = [TypeOfArray](count: NumbeOfItems, repeatedValue: Value)
or
var myarray:[Int] = [29, 17, 10]
or
var myarray:Array<Int> = Array()
Example:
var language = ["C", 'language","Java"] var num = [Int](count: 5, repeatedValue: 0)
Now some of the commonly used array properties are:
- Array.count Property
- Array.first Property
- Array.last Property
- Array.isEmpty Property
count Property
count property is used to count the total number of elements either be it numbers or strings present in the given array.
Syntax:
Array.count
Example:
Swift
// Swift program to illustrate the use of count property // Creating and initializing array variables let myArray1:[ Int ] = [23, 45, 67, 78, 65, 32, 34] let myArray2:[ String ] = [ "C++" , "Java" , "Python" , "Perl" , "Go" ] let myArray3:[ Int ] = [3, 45, 3, 86, 50] // Using count property to count the // elements present in each array let res1 = myArray1. count let res2 = myArray2. count let res3 = myArray3. count // Displaying the total count print ( "Total elements present in first array:\(res1)" ) print ( "Total elements present in second array:\(res2)" ) print ( "Total elements present in third array:\(res3)" ) |
Output:
Total elements present in first array:7 Total elements present in second array:5 Total elements present in third array:5
first Property
first property is used to find the first element either be it numbers or strings present in the specified array.
Syntax:
Array.first
Example:
Swift
// Swift program to illustrate the use of first property // Creating and initializing array variables let myArray1:[ Int ] = [23, 45, 67, 78, 65, 32, 34] let myArray2:[ String ] = [ "C++" , "Java" , "Python" , "Perl" , "Go" ] let myArray3:[ Int ] = [3, 45, 3, 86, 50] // Using first property to // find the first element // of the given array let res1 = myArray1.first let res2 = myArray2.first let res3 = myArray3.first // Displaying the first element print ( "First element of the first array:\(res1)" ) print ( "First element of the second array:\(res2)" ) print ( "First element of the third array:\(res3)" ) |
Output:
First element of the first array:Optional(23) First element of the second array:Optional("C++") First element of the third array:Optional(3)
last Property
last property is used to find the last element either be it numbers or strings present in the specified array.
Syntax:
Array.last
Example:
Swift
// Swift program to illustrate the use of last property // Creating and initializing array variables let myArray1:[ Int ] = [23, 45, 67, 78, 65, 32, 34] let myArray2:[ String ] = [ "C++" , "Java" , "Python" , "Perl" , "Go" ] let myArray3:[ Int ] = [3, 45, 3, 86, 50] // Using last property to find the last element // of the given array let res1 = myArray1.last let res2 = myArray2.last let res3 = myArray3.last // Displaying the last element print ( "Last element of the first array:\(res1)" ) print ( "Last element of the second array:\(res2)" ) print ( "Last element of the third array:\(res3)" ) |
Output:
Last element of the first array:Optional(34) Last element of the second array:Optional("Go") Last element of the third array:Optional(50)
isEmpty Property
isEmpty property is used to find whether the specified array is empty or not. This property will return true if the specified array is empty. Otherwise it will return false if the specified array is not empty.
Syntax:
Array.isEmpty
Example:
Swift
// Swift program to illustrate the use of isEmpty property // Creating and initializing array variables let myArray1:[ Int ] = [23, 45, 67, 78, 65, 32, 34] let myArray2:[ String ] = [ "C++" , "Java" , "Python" , "Perl" , "Go" ] let myArray3:[ Int ] = [ Int ]() // Using isEmpty property to check // whether the given array is empty or not let res1 = myArray1.isEmpty let res2 = myArray2.isEmpty let res3 = myArray3.isEmpty // Displaying the result print ( "Is the first array is empty?:\(res1)" ) print ( "Is the second array is empty?:\(res2)" ) print ( "Is the third array is empty?:\(res3)" ) |
Output:
Is the first array is empty?:false Is the second array is empty?:false Is the third array is empty?:true