javascript this explained code example

Example 1: javascript this

// In web browsers, the window object is also the global object:
console.log(this === window); // true

a = 37;
console.log(window.a); // 37

this.b = "MDN";
console.log(window.b)  // "MDN"
console.log(b)         // "MDN"

Example 2: use of this keyword in js

The JavaScript this keyword refers to the object it belongs to. 
It has different values depending on where it is used: In a method, 
this refers to the owner object. Alone, this refers to the global 
object.

Example 3: js this in object

var wF = {
    w : 560,
    h : function() { return (312 - 42) / (560 / this.w) + 42; }
};

alert(wF.h())

Example 4: how to use this in js

// In web browsers, the window object is also the global object:
console.log(this === window); // true

a = 37;
console.log(window.a); // 37

this.b = "MDN";
console.log(window.b)  // "MDN"
console.log(b)         // "MDN"