Question

I’m trying to understand the format of the Javascript functions that jQuery, among other people, use.

For instance jQuery(arg).hide() or $("#obj").hide

I’d like to write similar format functions but I don’t understand how.

I know how to write

function myFunc(args) {
}

but I don’t understand the second part ie the .hide()
is that a function within a function?

thanks for any help

Answer 1

It’s called method chaining. The way to achieve this is for your first function to return an object, so the second function can be called as a method on that object.

The standard way to do this style of programming is to always return the same type of object, so for example, jQuery always returns a jQuery object representing a collection of HTML nodes. If one of the calls modifies the collection then the next call will be on that collection. That’s how you can do something like $('#myid').parent().hide();. $('#myid') returns a jQuery object representing the #myid element and .parent() returns a jQuery object representing the parent element of #myid. .hide() returns the same object, so you could then call another method on the same object if you wanted.