This usage of javascript

1. This in the Global Code

This in the global context, its value is the global object itself, which is the window object in the browser, as shown in.

Look at the following examples:

//Global Scope
//The implicit property of the global object
varFOO1 = "ABC";
Console.log ( This. foo1 = = window.foo1); Console.log (FOO1); Console.log ( This. foo1); Console.log (WINDOW.FOO1);//true ABC ABC abc

//The implicit property of the global object
Foo2 = "Def";
Console.log ( This. Foo2 = = Window.foo2); Console.log (FOO2); Console.log ( This. Foo2); Console.log (WINDOW.FOO2);//true def def def

//The explicit property of the global object
This. Foo3 = "GH";
Console.log ( This. Foo3 = = Window.foo3); Console.log (FOO3); Console.log ( This. Foo3); Console.log (WINDOW.FOO3);//true gh gh gh

2.

This usage of javascript