JavaScript Map values()
Syntax & Examples
Map.values() method
The values() method of the Map object in JavaScript returns a new Iterator object that contains the values for each element in the Map object in insertion order.
Syntax of Map.values()
The syntax of Map.values() method is:
values()
This values() method of Map returns a new Iterator object that contains the values for each element in the Map object in insertion order.
Return Type
Map.values() returns value of type Iterator
.
✐ Examples
1 Using values() to iterate over a Map
In JavaScript, we can use the values()
method to get an iterator object and use it to iterate over the values of a Map.
For example,
- Create a new Map object
map
with initial key-value pairs. - Use the
values()
method to get an iterator objectiterator
for themap
. - Use a
for...of
loop to iterate over theiterator
and log each value to the console usingconsole.log()
.
JavaScript Program
const map = new Map([['a', 1], ['b', 2], ['c', 3]]);
const iterator = map.values();
for (const value of iterator) {
console.log(value);
}
Output
1 2 3
2 Using values() to convert a Map to an array of values
In JavaScript, we can use the values()
method to convert a Map object to an array of values.
For example,
- Create a new Map object
map
with initial key-value pairs. - Use the
values()
method to get an iterator objectiterator
for themap
. - Convert the
iterator
to an array using theArray.from()
method and store it in the variablearrayOfValues
. - Log
arrayOfValues
to the console usingconsole.log()
.
JavaScript Program
const map = new Map([['a', 1], ['b', 2], ['c', 3]]);
const iterator = map.values();
const arrayOfValues = Array.from(iterator);
console.log(arrayOfValues);
Output
[ 1, 2, 3 ]
3 Using values() with a Map of objects
In JavaScript, we can use the values()
method to iterate over a Map object containing objects as values.
For example,
- Create a new Map object
map
with initial key-value pairs where values are objects. - Use the
values()
method to get an iterator objectiterator
for themap
. - Use a
for...of
loop to iterate over theiterator
and log each value to the console usingconsole.log()
.
JavaScript Program
const map = new Map([
['person1', { name: 'John' }],
['person2', { name: 'Jane' }]
]);
const iterator = map.values();
for (const value of iterator) {
console.log(value);
}
Output
{ name: 'John' } { name: 'Jane' }
Summary
In this JavaScript tutorial, we learned about values() method of Map: the syntax and few working examples with output and detailed explanation for each example.