JS Practice — Built-in Objects

Object.keys() — array-like objects

📖 Usage Example

// Get array of own enumerable property names
const obj = { a: 1, b: 2, c: 3 }
Object.keys(obj)   // → ['a', 'b', 'c']

Use Object.keys() to get an array of an object's own enumerable property names for iteration or counting.

Object.keys() — arrays and array-like objects

Object.keys() also works on arrays, returning the index strings as keys.

Challenge: Use Object.keys() on an array to get its index keys.

💡 Hints (1)