quotes or no quotes inside two brackets?

Hi!

If you use the bracket notation then you should use quotes. Here's a little example for you.

var object = {
  'one': 1,
  'two': 2
};

// you should do this
object['one'];

// and not this
object[one];

// but you could also do this
object.one;

Hope it helps!

No problem!

It would still be the same. So you have to use quotes with the bracket notation no matter what. Let me write another example to clear things up.

var object = {
  myFriends: 10,
  'my friends': 10  
};

// the quotes only matter when the property name isn't a valid JavaScript variable name
object.myFriends;
object['myFriends'];
object['my friends'];

// you can't do this
object.my friends;

As you can see in the previous example the quotes around object's property names matter only if the property name is not a valid JavaScript variable name.

Hopefully this clears things up a little!

This definitely clears things up! One of the quiz questions in this Object-Oriented JS tutorial threw me off. It asked which notation of Object/property was incorrect. I chose the one that seemed to me to be incorrect, but the system said that I got it wrong - but now that you've explained it, I see that I was right - it was var key = "name"; cat[key] ....that's the way the option was written, without quotes around the key property in the square brackets. But the system treated this as a correct notation?!

Anyway, thank you again!

I get why you got confused now that you told the question. The way the system did it is actually a correct way too. The property of the object is not key but it's actually name. When you write key inside the brackets without the quotes you actually reference to a variable. Let's write another example.

var key = 'name';

var object = {
  name: 'John'
};

// now when you do this
object[key];

// it's exactly the same thing as doing this
object['name'];

This happens because key is a variable which has a string name. So basically you can think of it so that the variable key gets replaced with the string name. Sorry I might just be confusing you more.

So in var key = 'name' is "name" a property because var key doesn't have a visible property like var object, so whatever var key is equal to, that value would automatically be its property?

i.e. would these two examples be interchangeable?

object[property] and var object = "property"

Thanks, Markus!