JavaScript LogoA popular saying in the Real Estate business is: “Location, location, location!” Well, in JavaScript, it’s all about “context”. When you want to leverage the very powerful keyword: “this”, then understanding the current context is critical.

So, those experienced with native JavaScript should be comfortable with the concept of context (If you are not, take a moment to brush up on this subject; it’s important.) When you need to specify context, you would normally use the .call() or .apply() methods. The jQuery folks have also provided a way to accomplish this with their .proxy() method. This method takes two arguments, which are: the function to be executed and the object whose context should be targeted. Any additional arguments are optional and are passed to the function that is executed.

Example # 1

In Example # 1, we have created two simple objects: “foo” and “bar”. Note that each object has one property named “music”. Next, we set up two click event handlers. In each case, we execute the “handler” function. And that function makes reference to “this”. If we were to run that function by itself, the output of the alert would be “undefined”, because when doing that, “this” refers to the window object, which at this time has no property named “music”.

So, by using the jQuery.proxy() method, we specify the context within which the “handler” function should be executed.

Here is the JS Fiddle link for Example # 1:

Example # 2

In Example # 2, we have taken our cause to the DOM. We first create a function named toggleColor, which when passed a class name, will toggle that class name.

Next, we set up two click event handlers. In each case, we leverage jQuery.proxy(), to call the “toggleColor” function, and specify the context within which it should run. We’re also specifying the class name to be passed to that function.

Here is the JS Fiddle link for Example # 2:


In this article, we learned about the jQuery.proxy() method. In doing so, we discussed how it is used to specify the context within which a function should be executed. First we demonstrated how you can leverage this function using object literals. We then showed how you can do so by using DOM elements.

Helpful Links for the jQuery.proxy() method