How to Print a Map in Kotlin

How to Print a Map in Kotlin ?

Answer

To print a map in Kotlin, you can iterate over the map using the forEach method, a for loop, or the entries property to print each key-value pair.

✐ Examples

1 Printing a Map Using forEach Method

We can print a map in Kotlin by iterating over the map using the forEach method and printing each key-value pair.

For example,

We start by declaring and initializing a map named myMap with some key-value pairs. In this example, the map has string keys and integer values.
We use the forEach method to iterate over each key-value pair in the map. The forEach method takes a lambda expression that defines the operation to be performed on each element.
Inside the lambda expression, we print the key and value of each pair using the println function.

Kotlin Program

fun main() {
    // Declare and initialize a map
    val myMap: Map<String, Int> = mapOf(
        "one" to 1,
        "two" to 2,
        "three" to 3
    )

    // Print the map using forEach method
    myMap.forEach { (key, value) ->
        println("$key: $value")
    }
}

Output

one: 1
two: 2
three: 3

2 Printing a Map Using for Loop

We can print a map in Kotlin by iterating over the map using a for loop and printing each key-value pair.

For example,

We start by declaring and initializing a map named myMap with some key-value pairs. In this example, the map has string keys and integer values.
We use a for loop to iterate over the entry set of the map. The loop variable entry represents each key-value pair in the map as a Map.Entry object.
Inside the loop, we print the key and value of each pair using the println function.

Kotlin Program

fun main() {
    // Declare and initialize a map
    val myMap: Map<String, Int> = mapOf(
        "one" to 1,
        "two" to 2,
        "three" to 3
    )

    // Print the map using a for loop
    for ((key, value) in myMap) {
        println("$key: $value")
    }
}

Output

one: 1
two: 2
three: 3

3 Printing a Map Using entries Property

We can print a map in Kotlin by iterating over the map using the entries property and printing each key-value pair.

For example,

We start by declaring and initializing a map named myMap with some key-value pairs. In this example, the map has string keys and integer values.
We use the entries property to get a set of the map's key-value pairs. Each entry in the set is a Map.Entry object containing a key and a value.
We use a for loop to iterate over the set of entries. The loop variable entry represents each key-value pair in the map.
Inside the loop, we print the key and value of each pair using the println function.

Kotlin Program

fun main() {
    // Declare and initialize a map
    val myMap: Map<String, Int> = mapOf(
        "one" to 1,
        "two" to 2,
        "three" to 3
    )

    // Print the map using entries property
    for (entry in myMap.entries) {
        println("${entry.key}: ${entry.value}")
    }
}

Output

one: 1
two: 2
three: 3

Summary

In this tutorial, we learned How to Print a Map in Kotlin language with well detailed examples.

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