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Adding Custom Functions to Your WordPress Theme’s functions.php

To enhance the functionality of your WordPress site, you can add custom functions like get_popular_posts_by_comment_count to your theme’s functions.php file. This file acts as the backbone of your WordPress theme, enabling you to introduce new features or alter existing behaviors.

Here’s how to safely add a custom function to your theme:

Step 1: Access Your Theme Files

Access your WordPress theme files through one of the following methods:

  • Via WordPress Admin Panel: Navigate to Appearance > Theme Editor from your WordPress dashboard. Here, you can directly edit the functions.php file of your active theme.
  • Via FTP or File Manager: Use an FTP client (like FileZilla) or your hosting provider’s file manager. Access the WordPress installation directory at /wp-content/themes/your-theme/, replacing your-theme with the name of your active theme.

Step 2: Edit functions.php

Locate and open the functions.php file:

  • In WordPress Admin Panel: Select the functions.php file from the list in the Theme Editor.
  • Using FTP or File Manager: Download the functions.php file and open it with a text editor that supports syntax highlighting, such as Notepad++ or Visual Studio Code.

Step 3: Add the Code (copy and paste from above.)

  • Scroll to the end of the functions.php file to avoid interfering with existing functions.
  • Paste the custom function code at the end of the file. Ensure you do not overwrite any existing code.
  • Add Comments: Document your changes with comments to explain the function’s purpose, making it easier for future modifications or troubleshooting.

Note: Direct modifications to the theme files can be risky. To prevent issues during theme updates or to avoid breaking your site, consider using a child theme for such customizations.

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About the Author: Bernard Aybout (Virii8)

I am a dedicated technology enthusiast with over 45 years of life experience, passionate about computers, AI, emerging technologies, and their real-world impact. As the founder of my personal blog, MiltonMarketing.com, I explore how AI, health tech, engineering, finance, and other advanced fields leverage innovation—not as a replacement for human expertise, but as a tool to enhance it. My focus is on bridging the gap between cutting-edge technology and practical applications, ensuring ethical, responsible, and transformative use across industries. MiltonMarketing.com is more than just a tech blog—it's a growing platform for expert insights. We welcome qualified writers and industry professionals from IT, AI, healthcare, engineering, HVAC, automotive, finance, and beyond to contribute their knowledge. If you have expertise to share in how AI and technology shape industries while complementing human skills, join us in driving meaningful conversations about the future of innovation. 🚀