set array = one dimension's values of multidimensional object array

Question

I have an Array() of Object()s with keys firstKey and secondKey.

Does a function exist that can set a var equal to an Array() of all of firstKeys' values only?

If so, what is it? Libs & plugins welcome.

Answer 1

You can use the Array.map() function:

var newArr = objects.map(function(w){ return w.firstKey; });