How to declare and initialize an array in Kotlin with example

This tutorial explains about multiple ways to declare and initialize an array of different values with examples.

Arrays in Kotlin are declared with a type of Array class, It contains size property and set and get functions

How to declare array in Kotlin

Arrays can be declared with multiple ways.

  • one way using Array constructor

Arrays can be declared with predefined size as given below


Array(size){default initialized values}

Here is an example

    var array = Array<Int>(4){0} //[0, 0, 0, 0]

The above syntax creates an array of Int type with a size of 4 elements, and each element is initilized with default value.

  • Another way using arrayOf function arrayOf functions is a generic function, accepts values,
var numbers = arrayOf("one","two","three","four","five")

compiler infer the Type of the Array based on the values of an Array, Here is it is a String or super class of this.

The same can be declared type after variable declaration

var numbers: Array<String> = arrayOf("one","two","three","four","five")

You can replace arrayOf

var numbers = arrayOf<String>("one","two","three","four","five")