Prerequisite:
— Understand JavaScript’s “this” With Ease, and Master It.
— JavaScript Objects
— Understand JavaScript Closures
(This is an intermediate to advanced topic)
Duration: About 40 minutes.
Functions are objects in JavaScript, as you should know by now, if you have read any of the prerequisite articles. And as objects, functions have methods, including the powerful Apply, Call, and Bind methods. On the one hand, Apply and Call are nearly identical and are frequently used in JavaScript for borrowing methods and for setting the this value explicitly. We also use Apply for variable-arity functions; you will learn more about this in a bit.
On the other hand, we use Bind for setting the this value in methods and for currying functions.
We will discuss every scenario in which we use these three methods in JavaScript. While Apply and Call come with ECMAScript 3 (available on IE 6, 7, 8, and modern browsers), ECMAScript 5 (available on only modern browsers) added the Bind method. These 3 Function methods are workhorses and sometimes you absolutely need one of them. Let’s begin with the Bind method.
JavaScript’s Bind Method
We use the Bind () method primarily to call a function with the this value set explicitly.
