Get an Object's Keys as Array in JavaScript

Get an Object's Keys as Array in JavaScript #

To get the keys of an object as an array, use the Object.keys() method, passing it the object as a parameter. The method returns an array containing the object's property names in the same order as provided by a for ... in loop.

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const obj = {id: 1, country: 'Chile', city: 'Santiago'};

const keys = Object.keys(obj);

// 👇️ ['id', 'country', 'city']
console.log(keys);

The only parameter the Object.keys method takes is the object of which to get the property names.

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const obj = {id: 1, country: 'Chile', city: 'Santiago'};

const keys = [];

for (const key in obj) {
  keys.push(key);
}

// 👇️ ['id', 'country', 'city']
console.log(keys);

In the code snippet we use the for...in loop to iterate over all of the object's keys. On each iteration we push the key into the keys array to achieve the same result as with the Object.keys method.

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const arr = ['one', 'two', 'three'];

const keys = Object.keys(arr);

// 👇️ ['0', '1', '2']
console.log(keys);

Further Reading #

• Get the Number of Keys in an Object using JavaScript
• Check if an Object contains a Function in JavaScript
• Get a Random Property from an Object in JavaScript
• Get a Random Property from an Object in JavaScript
• How to get the Length of an Object in JavaScript
• Check if a Map has an Object Key using JavaScript
• How to Rename an Object's Key in JavaScript
• Check if a Value is an Object using JavaScript
• Convert an Object to an Array using JavaScript
• Convert a JSON String to Object using JavaScript
• Convert an Array to an Object using JavaScript
• Create an Object from Two Arrays in JavaScript
• Cannot convert undefined or null to Object in JS