Iterate over a list in Kotlin

This article explores different ways to iterate over a list in Kotlin.

1. Using `toString()` function

If you want to display the list’s contents, you can simply print the string representation of the list using the toString() function.

fun main() {

val list: List<String> = listOf("One", "Two", "Three")

println(list.toString())

}

You can use a special iterator ListIterator, that additionally allows bi-directional access. To get a normal iterator, use iterator() function.

fun main() {

val list: List<String> = listOf("One", "Two", "Three")

val itr = list.listIterator() // or, use `iterator()`

while (itr.hasNext()) {

println(itr.next())

}

Since List is an ordered collection, you can use index-based for-loop to access elements by their index in the list.

fun main() {

val list = listOf("One", "Two", "Three")

for (i in list.indices) {

println(list[i])

}

The for-loop also has another variation called the foreach loop, which can be used to loop through the list.

fun main() {

val list = listOf("One", "Two", "Three")

for (s in list) {

println(s)

}

Finally, you can use the forEach() function that performs the given action on each list element.

fun main() {

val list: List<String> = listOf("One", "Two", "Three")

list.forEach { println(it) }

}

That’s all about iterating over a list in Kotlin.