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WordPress Plugin Development Cookbook

You're reading from   WordPress Plugin Development Cookbook Explore the complete set of tools to craft powerful plugins that extend the world's most popular CMS

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Product type Paperback
Published in Mar 2022
Publisher Packt
ISBN-13 9781801810777
Length 420 pages
Edition 3rd Edition
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Author (1):
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Yannick Lefebvre Yannick Lefebvre
Author Profile Icon Yannick Lefebvre
Yannick Lefebvre
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Toc

Table of Contents (15) Chapters Close

Preface 1. Chapter 1: Preparing a Local Development Environment 2. Chapter 2: Plugin Framework Basics FREE CHAPTER 3. Chapter 3: User Settings and Administration Pages 4. Chapter 4: The Power of Custom Post Types 5. Chapter 5: Customizing Post and Page Editors 6. Chapter 6: Extending the Block Editor 7. Chapter 7: Accepting User Content Submissions 8. Chapter 8: Customizing User Data 9. Chapter 9: Leveraging JavaScript, jQuery, and AJAX Scripts 10. Chapter 10: Adding New Widgets to the WordPress Library 11. Chapter 11: Fetching, Caching, and Regularly Updating External Site Data 12. Chapter 12: Enabling Plugin Internationalization 13. Chapter 13: Distributing Your Plugin on WordPress.org 14. Other Books You May Enjoy

Using a local library to implement a CAPTCHA on user forms

As discussed in the previous recipe, Implementing a CAPTCHA on user forms using an online service, adding a CAPTCHA to visitor-facing forms helps reduce unwanted submissions to a website. After seeing how to integrate an online third-party service, this recipe shows how to download and integrate a local PHP script to generate and validate CAPTCHA images locally.

Getting ready

You should be running the final version of the Book Reviews plugin created in Chapter 4, The Power of Custom Post Types. You should also have already followed the Sending email notifications upon new submissions recipe. You should not have any Google reCAPTCHA code from the previous recipe.

Alternatively, you can get the resulting files from the book's GitHub page (ch4/ch4-book-reviews/ch4-book-reviews-v12.php and ch7/ch7-book-review-user-submission/ch7-book-review-user-submission-v3.php). The ch7-book-review-user-submission-v3.php file should...

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