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Object.entries()

The Object.entries() static method returns an array of a given object's own enumerable string-keyed property key-value pairs.

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Syntax

js
Object.entries(obj)

Parameters

obj

An object.

Return value

An array of the given object's own enumerable string-keyed property key-value pairs. Each key-value pair is an array with two elements: the first element is the property key (which is always a string), and the second element is the property value.

Description

Object.entries() returns an array whose elements are arrays corresponding to the enumerable string-keyed property key-value pairs found directly upon object. This is the same as iterating with a for...in loop, except that a for...in loop enumerates properties in the prototype chain as well. The order of the array returned by Object.entries() is the same as that provided by a for...in loop.

If you only need the property keys, use Object.keys() instead. If you only need the property values, use Object.values() instead.

Examples

Using Object.entries()

js
const obj = { foo: "bar", baz: 42 };
console.log(Object.entries(obj)); // [ ['foo', 'bar'], ['baz', 42] ]

const arrayLike = { 0: "a", 1: "b", 2: "c" };
console.log(Object.entries(arrayLike)); // [ ['0', 'a'], ['1', 'b'], ['2', 'c'] ]

const randomKeyOrder = { 100: "a", 2: "b", 7: "c" };
console.log(Object.entries(randomKeyOrder)); // [ ['2', 'b'], ['7', 'c'], ['100', 'a'] ]

// getFoo is a non-enumerable property
const myObj = Object.create(
  {},
  {
    getFoo: {
      value() {
        return this.foo;
      },
    },
  },
);
myObj.foo = "bar";
console.log(Object.entries(myObj)); // [ ['foo', 'bar'] ]

Using Object.entries() on primitives

Non-object arguments are coerced to objects. undefined and null cannot be coerced to objects and throw a TypeError upfront. Only strings may have own enumerable properties, while all other primitives return an empty array.

js
// Strings have indices as enumerable own properties
console.log(Object.entries("foo")); // [ ['0', 'f'], ['1', 'o'], ['2', 'o'] ]

// Other primitives except undefined and null have no own properties
console.log(Object.entries(100)); // []

Converting an Object to a Map

The Map() constructor accepts an iterable of entries. With Object.entries, you can easily convert from Object to Map:

js
const obj = { foo: "bar", baz: 42 };
const map = new Map(Object.entries(obj));
console.log(map); // Map(2) {"foo" => "bar", "baz" => 42}

Iterating through an Object

Using array destructuring, you can iterate through objects easily.

js
// Using for...of loop
const obj = { a: 5, b: 7, c: 9 };
for (const [key, value] of Object.entries(obj)) {
  console.log(`${key}${value}`); // "a 5", "b 7", "c 9"
}

// Using array methods
Object.entries(obj).forEach(([key, value]) => {
  console.log(`${key}${value}`); // "a 5", "b 7", "c 9"
});

Specifications

Browser compatibility

Desktop Mobile Server
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android Deno Node.js
entries 54 14 47 41 10.1 54 47 41 10.3 6.0 54 1.0 7.0.0

See also

© 2005–2023 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/entries