How to Remove a Key-Value Pair from a Map in JavaScript - Step by Step Examples

How to Remove a Key-Value Pair from a Map in JavaScript ?

Answer

To remove a key-value pair from a map in JavaScript, you can use the delete method. This method allows you to remove the key-value pair associated with the specified key.

✐ Examples

1 Removing a Key-Value Pair Using delete Method

We can remove a key-value pair from a map in JavaScript using the delete method, which removes the key-value pair associated with the specified key.

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 delete method to remove the key-value pair associated with the key 'two'. The delete method removes the key-value pair from the map.
We print the contents of the map to the console using the console.log function to verify that the key-value pair has been removed.

JavaScript Program

const myMap = new Map([
    ['one', 1],
    ['two', 2],
    ['three', 3]
]);

// Remove a key-value pair using delete method
myMap.delete('two');

// Print the contents of the map
console.log(myMap);

Output

Map(2) { 'one' => 1, 'three' => 3 }

2 Handling Key Not Found Using delete Method

We can handle the case where a key is not found in a map in JavaScript using the delete method, which returns false if the key is not present.

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 delete method to attempt to remove the key-value pair associated with the key 'four'. The delete method returns false if the key is not found.
We print the contents of the map to the console using the console.log function to verify that the map is unchanged.

JavaScript Program

const myMap = new Map([
    ['one', 1],
    ['two', 2],
    ['three', 3]
]);

// Attempt to remove a non-existent key-value pair using delete method
const result = myMap.delete('four');

// Print the result and the contents of the map
console.log(result); // false
console.log(myMap);

Output

false
Map(3) { 'one' => 1, 'two' => 2, 'three' => 3 }

3 Removing Multiple Key-Value Pairs Using delete Method

We can remove multiple key-value pairs from a map in JavaScript using the delete method, which removes the key-value pairs associated with the specified keys.

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 delete method to remove the key-value pairs associated with the keys 'one' and 'three'. The delete method removes the key-value pairs from the map.
We print the contents of the map to the console using the console.log function to verify that the key-value pairs have been removed.

JavaScript Program

const myMap = new Map([
    ['one', 1],
    ['two', 2],
    ['three', 3]
]);

// Remove multiple key-value pairs using delete method
myMap.delete('one');
myMap.delete('three');

// Print the contents of the map
console.log(myMap);

Output

Map(1) { 'two' => 2 }

Summary

In this tutorial, we learned How to Remove a Key-Value Pair from a Map in JavaScript language with well detailed examples.

◀ Previous Next ▶

JavaScript Tutorials

JavaScript How-Tos

How to Remove a Key-Value Pair from a Map in JavaScript - Step by Step Examples