Quirky JavaScript Object Access

My friend asked me a simple JavaScript question last night… or so I thought.

The premise is that we have a javascript object like this:

Now the question is, how do you access that items  array?

From what I know:

  • An object’s keys are stringified so that they are strings.
  • Using object.X  is the same as writing object['X'] .

So, I told my friend that we can access that items  array by using object.1.items  or  object['1'].items .

However, object['1'].items worked, while object.1.items threw an error! To my surprise, object[1].items  also worked!

Now let’s say the javascript object is like this:

In this second case, I tested it in the Chrome browser console and confirmed that it is how I originally thought it would work: object['one'].items  and object.one.items  both work (and object[one].items  does not work).

I think I will just use the object['X']  format since it works in both cases: when the key is a number and when it is a word.

I still don’t know the reason for the quirkiness when the key is an integer, so feel free to leave a comment and let me know!