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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
231,186 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").