JavaScript entries()

The entries() method in JavaScript Maps returns an iterator containing each key–value pair in insertion order.

Syntax

map.entries();

Parameters:

The .entries() method takes no parameters.

Return value:

An iterator object that contains the [key, value] pairs for each element in the Map, in insertion order.

Note: If the Map object is empty, then entries() returns an empty iterator object.

Example

In this example, a Map’s key-value pairs are iterated using for...of:

const animals = new Map([
  ['cat', 1],
  ['dog', 2],
  ['horse', 3],
  ['eagle', 4],
  ['bear', 5],
  ['coyote', 6],
]);

const iterator = animals.entries();

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

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The output produced will be:

key: cat, value: 1
key: dog, value: 2
key: horse, value: 3
key: eagle, value: 4
key: bear, value: 5
key: coyote, value: 6

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Codebyte Example

In this example, a Map is used to track car inventory, search for a specific car, and update the inventory and wallet when a purchase is made:

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