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JavaScript

Richard Verbraak
Richard Verbraak
7,739 Points

Accessing objects with . and []

I'm confused as to how you can access an objects property / key with the 2 different methods.

Example from FCC where I just changed the first key name for testing.

var testObj = {
  name: "hamburger",
  "my side": "veggies",
  "the drink": "water"
};

var entreeValue = testObj.name;
console.log(entreeValue);

This logs hamburger for me which I get but why is it that I get undefined back when I use test.Obj[1]. Shouldn't this return hamburger which is indexed on 1?

I thought objects were similiar to arrays? Do they not have an index like an array? Or am I just confusing the 2 because I'm not sure when you would use an array over objects or vice-versa.

I'd appreciate it A LOT if someone could clear the differences up.

1 Answer

Steven Parker
Steven Parker
228,978 Points

Using the bracket notation for attribute access might look like indexing but it's a bit different. Instead of using a numeric index as with arrays, brackets for accessing attributes contain the name of the attribute as a string.

So the bracket equvalent of   testObj.name   would be   testObj["name"].