Question

My question is dead simple.

I just casually discovered that once you have defined a property with this. into an object, you don’t need to prepend this. anymore when you want to call them.

So this. is really meant to be used ad definition time, like var?

I found it my self shortly after, i was referencing the window object with this. since i called my object without using new, so like it was a function.

One extra question, maybe for comments. Inside the main object, if i create a new object, and use this during the object definition, this this what will be referring to?

Answer 1

No, unless the context of this is a global object, such as window. Take the following example:

function Foo(bar) {
    this.data = bar;
    console.log(this.data); // OK
    console.log(data); // ReferenceError
}

In this example, you’ll get a ReferenceError: data is not defined on the first console.log(data), unless, data is a global variable. To access the instance’s public member, you have to use this.data.

References:

• Understanding JavaScript’s this keyword
• The this keyword