How to Run JavaScript in Visual Studio Code: An In-Depth Guide

As a long-time full-stack developer and coding instructor, Visual Studio Code is my editor of choice for JavaScript development. VS Code offers exceptional JavaScript support and an intuitive workflow that enhances productivity.

In this comprehensive guide, we will cover multiple methods for executing JavaScript code in VS Code using its built-in debugger and integration with Node.js. We’ll also compare VS Code to other JavaScript editors and look at useful tips and extensions.

Why Visual Studio Code for JavaScript?

Before we get to running JavaScript, why use VS Code in the first place compared to other editors? What makes VS Code so popular for JavaScript development?

• VS Code is free, open source, and works across operating systems
• It has excellent JavaScript IntelliSense for smarter code completion
• Integrated debugging and Node.js support
• A rich extensions ecosystem to customize the editor
• Lightweight yet packed with advanced features
• Continually improved with monthly updates from Microsoft

StackOverflow’s 2021 survey found VS Code was the most popular development environment globally. For JavaScript specifically, over 50% of developers use VS Code – considerably higher than alternatives like WebStorm, Atom or Sublime Text.

So for flexibility, performance, and Node.js integration, VS Code stands out as the intelligent choice for JavaScript.

Installing Node.js Runtime

To execute JavaScript locally, you need the Node.js runtime environment installed. Here‘s why:

The JavaScript language on its own cannot run standalone without a host runtime. Browsers provide this runtime for client-side JavaScript executed in Web pages. For running JavaScript outside a browser on your desktop, Node.js fills that role.

Node.js interprets JavaScript code and provides system APIs like file I/O. This allows building desktop and server applications with JavaScript. Many tools in VS Code‘s JavaScript toolchain also rely on Node.js internally.

You can download Node.js installers for Windows, macOS, and Linux from nodejs.org. Make sure to install Node globally to make the node command accessible system-wide.

Verify successful installation from the terminal:

node --version

With Node.js installed, the local machine is ready to run JavaScript using VS Code.

Creating a JavaScript File

Open an empty folder in VS Code. This will be your workspace. Next, create a script.js file and add the following code:

function printMessage() {
  console.log("Hello from VS Code!"); 
}

printMessage();

Here we have a simple function that prints a message, called during execution.

With the file open in the editor, there are different ways to run this script.

Running JavaScript with Node.js

Node.js provides a command to execute JavaScript files on the desktop. From VS Code‘s terminal, type:

node script.js

This will run script.js using the locally-installed node runtime. You should see the "Hello from VS Code!" message printed.

The full sequence is:

1. Developer types node script.js in terminal
2. node runtime loads and parses script.js
3. printMessage() function called; prints message
4. Runtime exits after code finishes execution

Being able to run code like this is invaluable for rapidly testing functionality as you code, without needing a browser.

Debugging JavaScript in VS Code

VS Code provides robust debugging for JavaScript both on Node.js and in-browser. Debugging allows stepping through code line-by-line to inspect application state and troubleshoot issues.

To debug our script:

1. Put a breakpoint by clicking the left gutter of a line number
2. Press F5 to launch debugger
3. Execution will pause at breakpoint

Once paused, we can analyze variables in debugger window, step through lines with F10, or hover functions to view stack traces. This rapid, iterative coding style makes building complex logic much easier.

The inline debugging experience saves enormous developer time over console logging everything. Features like hot restarting debug sessions while retaining variable state further boost efficiency.

Out of all JavaScript IDEs, VS Code‘s debugger with support for advanced breakpoints is second-to-none in usability.

Using CodeRunner Extension

The CodeRunner extension is another useful way to execute JavaScript in VS Code quickly.

After installing CodeRunner, running scripts is as easy as:

1. Open JavaScript file
2. Press Ctrl + Alt + N
3. Output appears immediately

By using CodeRunner, constant typing of node script.js is avoided. The extension automatically runs active JavaScript file when triggered. Additional perks like duration of script run help analyze performance.

Comparing JavaScript Editors

VS Code is far from the only code editor for JavaScript development. What sets it apart from other options?

• Atom – Open-source editor from GitHub team. Not as performant or fully-featured as VS Code.
• Webstorm – Premium JavaScript IDE packed with tools. Complex interface has learning curve.
• Sublime – Lightweight, customization-friendly editor. Lacks built-in debugger.
• Brackets – Made specifically for web design. Less suited for broader JS development.

For most JavaScript dev scenarios – be it web, Node.js or front-end frameworks – VS Code strikes the optimal blend of power, simplicity and customizability. The rich extension ecosystem makes adapting VS Code to specialized needs easy.

Top Tips for JavaScript Development in VS Code

Here are my top 5 tips to improve the JavaScript coding experience within VS Code:

1. Install ESLint for linting – Catch syntax and style issues early.

2. Use Quokka.js for rapid prototyping – Live output for code without running.

3. Enable code formatting via Prettier – Fix sloppy formatting automatically.

4. Adjust debugger settings for faster reloads – Set "Restart" instead of "Stop" on ending debug session.

5. Install keybinding cheat sheet – Display available shortcuts. Critical for productivity!

Integrating Source Control

An underrated ability of VS Code is its baked-in Git source control features. Developers can commit, pull, push, revert and merge code changes without leaving the editor.

JavaScript projects hosted remotely on GitHub or other platforms can be directly opened and edited within VS Code via the SCM integration. This simplifies project synchronization – critical when collaborating with other developers.

JavaScript Transpilers and Bundlers

For transpiling modern JavaScript to cross-browser friendly ES5 code, Babel is the leading choice. The Babel JavaScript VS Code extension provides syntax highlighting for .js files containing JSX code used in React development.

For bundling JavaScript modules into production-ready packages served to browsers, Webpack is invaluable. Once configured properly, Webpack + VS Code can build and bundle React apps without needing the command line.

Where To Go From Here?

In summary, whether you are new to JavaScript or a seasoned veteran, Visual Studio Code has all the bells and whistles necessary for end-to-end JS development:

✅ Debugging and profiling apps
✅ Running scripts via Node.js integration
✅ Extending functionality through extensions
✅ Built-in version control with Git

This guide just scratches the surface of everything VS Code offers. As you grow into advanced JavaScript frameworks like Angular, Vue.js or React, tools like IntelliSense and the debugger keep leveling up in utility.

For further learning, visit the official Node.js docs for tutorials. The VS Code JavaScript guide also covers more features like IntelliSense.

Now you have all the knowledge for running JavaScript in Visual Studio Code – happy coding! Let me know in the comments if you have any other VS Code pro tips.