Kotlin Tutorials

Kotlin Map get()
Syntax & Examples

Syntax of Map.get()

The syntax of Map.get() function is:

abstract operator fun get(key: K): V?

This get() function of Map returns the value corresponding to the given key, or null if such a key is not present in the map.


✐ Examples

1 Get value corresponding to specified key (present)

In this example,

  • We create a map named map1 containing pairs of numbers and characters.
  • We then retrieve the value corresponding to the key 2 using the get() function.
  • As 2 is present in the keys of map1, the corresponding value 'b' is returned.
  • We print the result to standard output.

Kotlin Program

fun main(args: Array<String>) {
    val map1 = mapOf(1 to 'a', 2 to 'b', 3 to 'c')
    val value1 = map1.get(2)
    println(value1)
}

Output

b

2 Get value corresponding to specified key (not present)

In this example,

  • We create a map named map2 containing pairs of characters and numbers.
  • We then attempt to retrieve the value corresponding to the key 'd' using the get() function.
  • As 'd' is not present in the keys of map2, null is returned.
  • We print the result to standard output.

Kotlin Program

fun main(args: Array<String>) {
    val map2 = mapOf('a' to 1, 'b' to 2, 'c' to 3)
    val value2 = map2.get('d')
    println(value2)
}

Output

null

3 Get value corresponding to specified key (present)

In this example,

  • We create a map named map3 containing pairs of strings and numbers.
  • We then retrieve the value corresponding to the key 'banana' using the get() function.
  • As 'banana' is present in the keys of map3, the corresponding value 2 is returned.
  • We print the result to standard output.

Kotlin Program

fun main(args: Array<String>) {
    val map3 = mapOf("apple" to 1, "banana" to 2, "cherry" to 3)
    val value3 = map3.get("banana")
    println(value3)
}

Output

2

Summary

In this Kotlin tutorial, we learned about get() function of Map: the syntax and few working examples with output and detailed explanation for each example.