09. jQuery's Other Async Methods

jQuery has a number of other methods that can be used to make asynchronous calls. These methods are:

• .get()
• .getJSON()
• .getScript()
• .post()
• .load()

Each one of these functions in turn calls jQuery's main .ajax() method. These are called "convenience methods" because they provide a convenient interface and do some default configuration of the request before calling .ajax().

Let's look at the .get() and .post() methods to see how they just call .ajax() under the hood.

Add a Breakpoint

With the project open in a browser:

1. load up DevTools

• open the Sources pane
• open the jQuery file
• add a breakpoint to line 8797
• reload the page (this will pause the code at the breakpoint you just made!)

The first time through the loop, the method variable will be get. This makes

jQuery[ method ] = function(...) { … }

become

jQuery[ 'get' ] = function( … ) { … }

which gives us the $.get() method!

On line 8807 you can see that this new jQuery[ 'get' ] function returns a call made to jQuery.ajax( … );! Notice that before the .ajax() call is run, the type property is set to the method variable (which is still'get'). So calling $.get() calls $.ajax() with some preset properties.

All this was for 'get'. This exact same code runs right after this for 'post'! So the code creates a jQuery[ 'post' ] function that will call jQuery.ajax( … ) and set the type property to 'post'.

Isn't it pretty cool how jQuery provides these convenience methods that just end up calling the main .ajax() method!?

Which Method Should You Use?

From the jQuery website:

It's often considered good practice to use the $.ajax() method over the jQuery provided convenience methods.