A McGraw Hill Book Plug-in PHP: 100 Power Solutions
By Robin Nixon (McGraw Hill 2010, ISBN 978-0071666596)

Home | About | Buy It | Download | Contact

Select Chapter: 1  2  3  4  5  6  7  8  9 10 11 12

Chapter 6: Plug-in 37 - Spam Catch

Even with a strong Captcha system in place you will still find users trying to manually spam your website. They tend to be people who discover your site through a very specific search engine query for which they would like their own site to also rank well, and they hope that by adding a link back to their site from yours this will happen. Using this plug-in you can specify a set of keywords that will trigger spam detection, and then use the level of spam certainty returned by the function to decide whether to ignore a user post.

The Figure shows an example message that has been given a suspected spam score of 22.