06. Peek inside $.ajax()

Ud109 AJAX L2 15 L Peek Inside $.Ajax()

We're about to dig into jQuery's source for a second. To do that, you need to:

  1. open up the project in a browser
  2. open up DevTools
  3. switch to the "Sources" pane
  4. open up the jquery.js file
    • in Chrome, you can open a specific file by searching for it with ctrl/command + P
  5. set a breakpoint on line 9036

_A breakpoint set in the jQuery source file right where new XMLHttpRequest object is created_

A breakpoint set in the jQuery source file right where new XMLHttpRequest object is created

Search For A Topic

Now that we've added the breakpoint, if we do a search, then the JavaScript code will run (which will use jQuery's .ajax() method!) and DevTools will pause when it hits the line with the breakpoint. So go ahead and do a search to cause the code to break at the breakpoint. Why not search for something exciting like "Volcanoes"!

_DevTools paused at breakpoint_

DevTools paused at breakpoint

Debugging in Chrome

TIP: If you've never done it before, debugging is a JavaScript application can seem like a complicated process. We'll be looking at the important parts of DevTools in this course, but if you're looking for a deeper dive, check out the following resources on Google's Developer site:

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