Kotlin List.contains() Function

The Kotlin List.contains() function returns true if element is found in the list, else false.

Syntax of List.contains()

The syntax of List.contains() function is

list.contains(element)
ParameterDescription
elementThe element which has to be checked if present in this list.

Return Value

ValueScenario
trueIf element is present in the list.
falseIf element is not present in the list.

Example 1: Check if List Contains Element

In this example, we will take a list of strings, list1, and a string, element. We will use list.contains() method to check if list1 contains element.

Kotlin Program

fun main(args: Array<String>) {
    val list1 = listOf("a", "b", "c", "d", "e", "f")
    val element = "e"
    val result = list1.contains(element)
    print("Is element present in list? $result")
}

Output

Is element present in list? true

Example 2: List.contains() – Element not in List

In this example, we will take a list of strings, list1, and a string that is not present in the list. We will call list1.contains() and find out the return value when element is not present in the list.

Kotlin Program

fun main(args: Array<String>) {
    val list1 = listOf("a", "b", "c", "d", "e", "f")
    val element = "m"
    val result = list1.contains(element)
    print("Is element present in list? $result")
}

Output

Is element present in list? false

Conclusion

In this Kotlin Tutorial, we learned how to check if a list contains a specific element, using Kotlin List.contains() function.