Error handling

So far we have only dealt with successful responses to Ajax requests, loading the page with new content when everything goes as planned. Responsible developers, however, should account for the possibility of network or data errors and report them appropriately. Developing Ajax applications in a local environment can lull developers into a sense of complacency since, aside from a possible mistyped URL, Ajax errors just don't happen locally. Unfortunately, the Ajax convenience methods such as $.get() and .load() do not provide an error callback argument themselves, so the global .ajaxError() method has been, at least in early versions of jQuery, the only way to handle errors with these methods. However, with the overhaul of jQuery's Ajax component in version 1.5, we now can chain success(), complete(), and error() callbacks to any Ajax function except .load(). For example, we can take the code from Listing 6.16 and change the URL to one that doesn't exist, we can test the error...