jQuery LogoOnce you have jQuery plugin basics down, it’s time to implement some best practices

In the previous post “jQuery Plugin Authoring – The Absolute Basics – Part I”, we to a detailed look at the architecture of a jQuery plugin. Now that you understand the building blocks, let’s discuss a few best practices. These techniques are considered standard for quality jQuery plugin authoring, and will dress you for success.

Protecting the Dollar Sign

Most jQuery consumers associate the dollar sign with jQuery. But that dollar sign is simply a shortcut to the jQuery object, which is a property of the window object. You could write all of your jQuery code without ever using the dollar sign, and simply “jQuery” instead. But most people prefer the dollar sign because it is of course quite a bit easier and faster to type.

But jQuery offers a “no conflict” mode that allows another library to take over the dollar sign. It is considered best practice to anticipate this scenario and pass the global jQuery object into the immediate function that wraps your plugin. This way, inside of the nice and safe sandbox of your plugin, you can use the dollar sign all you like, without the slightest concern for how it is being used in the global context.

Example # 1

In Example # 1, we pass the global jQuery object into the immediate function. The immediate function takes that jQuery object as “$”, so from there on we are free to use the dollar sign safely, even if jQuery is in no-conflict mode.


Method chaining is a popular technique in JavaScript. Many web developers use this technique when they leverage jQuery without even knowing it. How many time have you seen something like this:

$(SOME PARENT).find(SOME CHILD).CSS(“prop”,”val”).click();

What signifies the chaining activity is the fact that we have only one reference to the jQuery collection returned by $(SOME PARENT). Since each method used returns the jQuery object, we can use that return value to invoke another jQuery method, and so on. This is called “Chaining” method calls together.

It is considered best practice to allow method chaining when authoring your own jQuery plugin. Doing so is quite simple; you just need to return the jQuery object from each method.

Example # 2

In Example # 2, we return “this” from our plugin function. It’s important to note where the return statement is. Because the return statement occurs as the last line of code in our plugin’s function, the jQuery collection object is returned to the next method that wants to “chain”, without the need to re-state a jQuery collection.

Example # 3

In Example # 3, we have an example of method chaining in jQuery. Note that $(‘a’) only occurs once. That call to jQuery returns a jQuery collection object, which is returned from our jQuery plugin. As a result, the .attr() method can “chain” onto that return value and function properly.

Example # 4

In Example # 4, we have an even more complex example of method chaining. First we invoke “myPlugin”, and the the jQuery methods: .attr(), .css() and .click()

Here is a fully working JSFiddle.net link that demonstrates the best practices we have covered in this article. Be sure to click a few of the links to demonstrate the method chaining from example # 4:



In this article we discussed a few jQuery plugin authoring best practices. We covered how to safely use the dollar sign in your plugin code, even when jQuery is in no-conflict mode. We also covered how to implement method chaining.

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