Object.keys()

The Object.keys() method returns an array of a given object's own enumerable properties, in the same order as that provided by a for...in loop (the difference being that a for-in loop enumerates properties in the prototype chain as well).
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And this is how you iterate the keys of an array:

Object.keys(myArray).forEach(function (key) {
   // do something with obj[key]
});

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