How to Debug JavaScript Code Like a Pro: 5 Steps

Debugging the code is a necessary part of the daily work as a developer. Although debugging might be time-consuming and irritating, detecting and correcting problems in the code is essential. Given that JavaScript is one of the most often used programming languages, it's critical to have expert debugging skills.

 

1. Start with the "Debugger" Statement

 

All current browsers come with excellent debugging tools. Therefore, setting breakpoints inside the browser's debugger is often a smart idea if you encounter a client-side bug.

However, it can be time-consuming to locate the correct file and line number inside the debugger. In the available debugging tool, this statement will serve as a breakpoint, allowing to immediately begin debugging at the proper location.

 

2. Examine the Stack Trace 

Errors are frequently only the beginning. Underneath the surface is a coded route that caused the issue. As a result, it can be challenging to comprehend an inaccuracy on its own. The sequence of function calls leading up to the error is shown in the error stack. 

Debugging is made much simpler when the actual code path is visible.

The stack can be retrieved by typing an error stack into a JavaScript runtime Error object, which is a property. By explicitly exposing the stack, most debugging tools take care of this for you.

 

3. Keep Things in Mind

Frequently, variables with unexpected values can help find flaws. These values, however, might alter with time. Tracking a variable's current value using Watch is quite easy. Just add the variable of interest to the "watch" section of the debugging tools. The new value of a watched variable will be indicated whenever its value changes.

 

4. Observe Outside Requests

Since the introduction of the Jamstack, modern applications have become increasingly HTTP request-heavy. The XHR/Fetch part of the debugging tools can be used to streamline the debugging of external queries. You can either filter based on text snippets in the target URL or set a breakpoint on every request. Therefore, in the example below, a breakpoint is set off whenever a request is sent to a target that contains the string "zipcode-API".

 

5. Make Use of the IDE's Debugger.                                 

Although defects start in the source code, they frequently show up as a result of finished products like websites and mobile apps. Because of this, fixing bugs frequently necessitates frantically switching between the source code and the browser.

You might make advantage of the IDE's built-in debugger to get rid of this distraction. There are debuggers included in Visual Studio Code, the most well-known IDE, for Chrome, Edge, and Node.js. These built-in debuggers give the IDE essential debugging features like breakpoints, a stack trace, and variable watching. 

 

Conclusion

Debugging is a crucial step in the software development process, and JavaScript is especially prone to errors because it is a dynamic, interpreted language. Fortunately, you can debug the JavaScript code using a variety of methods and tools, including the developer console in the browser, variable inspection, stepping through the code, breakpoints, and exception catching. The one-stop shop for thorough and simple-to-follow lessons on a variety of programming and web development topics is TutorialWithExample.com.