Creating a Map

To create a new Map object, you can simply use the new keyword and call the Map constructor:

const myMap = new Map();

Adding and Accessing Values

To add a key-value pair to a Map, you can use the set() method:

myMap.set("name", "John");
myMap.set("age", 30);

To access a value based on a key, you can use the get() method:

const name = myMap.get("name");
console.log(name); // Output: "John"

You can also check if a key exists using the has() method:

const hasAge = myMap.has("age");
console.log(hasAge); // Output: true

Removing Values

To remove a specific key-value pair from a Map, you can use the delete() method:

myMap.delete("name");

You can also clear all key-value pairs in a Map using the clear() method:

myMap.clear();

Iterating over a Map

There are several ways to iterate over the key-value pairs in a Map.

1. Using the for...of loop:

for (const [key, value] of myMap) {
  console.log(`${key}: ${value}`);
}

1. Using the forEach() method:

myMap.forEach((value, key) => {
  console.log(`${key}: ${value}`);
});

Map Size

To get the number of key-value pairs in a Map, you can use the size property:

console.log(myMap.size); // Output: 1

Conclusion

The Map object in JavaScript provides a convenient way to store and manipulate key-value pairs. It offers various methods for adding, accessing, and removing values, as well as iterating over the entries. Understanding the basic syntax and usage of the Map object is essential for working with complex data structures in JavaScript.

[hashtags: #JavaScript #MapObject]