Object.keys(obj) -> [String...]

Treats any object as a Hash and fetches the list of its property names.

Note that the order of the resulting Array is browser-dependent (it relies on the for…in loop), and is therefore not guaranteed to follow either declaration or lexicographical order. Sort the array if you wish to guarantee order.

Examples

Object.keys()
// -> []

Object.keys({ name: 'Prototype', version: 1.5 }).sort()
// -> ['name', 'version']