Highlight.js Syntax Highlighting Demo

Highlight.js Syntax Highlighting Demo

Highlight.js is a lightweight JavaScript library that automatically detects and highlights syntax in code blocks on web pages. This demo loads Highlight.js via CDN, initializes it on page load, and showcases highlighted code in multiple languages like HTML, CSS, JavaScript, Java, and SQL. It’s essential for blogs, documentation, and tutorials to make code readable and professional. Use cases include developer sites, educational platforms, and any content with code snippets. Alternatives like Prism.js offer similar features with different themes and plugins.

What is Highlight.js?

Highlight.js parses <pre><code> blocks, detects the language from the class attribute (e.g., class="javascript"), and applies CSS classes for styling. It supports 180+ languages and works client-side without server processing.

In this demo, it’s set up with:

<link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/styles/vs.min.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/highlight.min.js"></script>
<script>hljs.initHighlightingOnLoad();</script>

Then, code blocks like:

<pre><code class="javascript">
var cars = ["BMW", "Volvo", "Saab"];
</code></pre>

Are automatically highlighted.

Use Cases

Highlight.js is ideal for:

  • Blogs and Tutorials: Displaying code examples clearly.
  • Documentation Sites: Like MDN or GitHub, for API references.
  • Educational Platforms: Online courses with code snippets.
  • Forums and Q&A: Stack Overflow-style code blocks.
  • Static Sites: Blogs built with Hugo or Jekyll.

It enhances readability, aids learning, and improves SEO by making content more engaging.

Alternatives for Code Display

Several libraries provide clean code highlighting:

  • Prism.js: Lightweight, supports more languages and plugins (e.g., line numbers, copy buttons). Better for customization.
  • CodeMirror: Full code editor with highlighting, used in IDEs like VS Code. Overkill for static display.
  • Monaco Editor: Microsoft’s editor (used in VS Code online), powerful but heavy.
  • Rainbow: Simple and fast, good for basic needs.
  • SyntaxHighlighter: Older but reliable, with many themes.

Choose based on needs: Highlight.js for simplicity, Prism for features, CodeMirror for editing.

Implementation Tips

Ensure code is in <pre><code class="language"> format. Use themes from Highlight.js for styling. For dynamic content, call hljs.highlightBlock(element) after adding code. This demo shows basic setup, easily integrable into any site.

Portfolio highlight.jsjavascriptcodesyntax-highlighting