Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript Understanding "this" in JavaScript

Mia Filisch
Mia Filisch
16,117 Points

What is the difference between the 2nd and 3rd use of `this` mentioned in this video?

In both usages, this refers to the object itself. In the 2nd use case, if I understand correctly, we're dealing with an object literal, and in the 3rd use case, with an object instantiated through a constructor function. But isn't the value this takes in both of these conceptually the same, i.e. the object itself, as a way of accessing / referencing its properties?

1 Answer

Steven Parker
Steven Parker
229,644 Points

You're right, these are both examples of "this" referring to an object. The difference is that in the second case, a method is being called on an existing object; and "this" refers to that object.

In the third case, a constructor function in being called to create a new object that does not already exist. So "this" refers to the object being constructed even though no object reference is made in the call itself (using "new").