July 2025
Beginner
768 pages
16h 54m
English
Content preview from PHP, MySQL, & JavaScript All-In-One For Dummies, 2nd Edition
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Chapter 5
Troubleshooting JavaScript Programs
IN THIS CHAPTER
Finding errors in your JavaScript code
Using JavaScript debuggers
Working around errors
A fact of life when working with any type of programming language is that there will always be errors as you develop your application code. Working with JavaScript is no different; there are plenty of opportunities for coding errors to cause all sorts of problems in your web applications. But don't worry, getting an error in your application isn't the end of the world. There are some simple tools at your disposal to help you find and fix those errors before your site visitors experience them. This chapter gives you some ideas for what to do when errors occur as you develop your applications and explains how to work your way through them.
Identifying Errors
There are times when your web application runs into an error that it's fairly obvious that something went wrong — something that was supposed to happen didn’t. Other times, however, program errors can be a little more subtle, such as altering the data in a way that’s not overly obvious until you analyze the output. These types of errors are dangerous because often, you don't even ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.