Several important attributes in JavaScript (this, constructor, prototype) Introduction _ basic knowledge

This indicates the current object. If this is used globally, it indicates the current page Object window. prototype is essentially a JavaScript Object, and constructor always points to the constructor that creates the current object. This
This indicates the current object. If this is used globally, it indicates the current page Object window. If this is used in the function, this indicates what is called Based on the object on which the function is called at runtime. We can also use the apply and call global methods to change the specific point of this in the function.
First, let's look at an example of using this in the global scope:

The Code is as follows: