JavaScript - Map Methods Part 4: Iterating Through a Map

1. keys() Method

The keys() method returns an iterator containing all the keys.

Example:

for (let key of planets.keys()) {

  console.log(key);

}

// Output:

// Earth

// Mars

2. values() Method

The values() method returns an iterator containing all the values.

Example:

for (let value of planets.values()) {

  console.log(value);

}

// Output:

// Third Planet

// Fourth Planet

3. entries() Method

The entries() method returns an iterator containing all key-value pairs as arrays.

Example:

for (let [key, value] of planets.entries()) {

  console.log(`${key}: ${value}`);

}

// Output:

// Earth: Third Planet

// Mars: Fourth Planet

4. Iteration with forEach()

The forEach() method executes a function for each key-value pair.

Example:

planets.forEach((value, key) => {

  console.log(`${key} => ${value}`);

});

// Output:

// Earth => Third Planet

// Mars => Fourth Planet