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PHP Enhancing a Simple PHP Application Cleaning URLs with Rewrite Rules Adding a Trailing Slash

Posted by Adam Zuckerberg
Adam Zuckerberg
22,248 Points

What is the difference between $ and % in a backreference?

I am confused. In one case in the rewrite rules, it looks like Andy uses /%1/ as a backreference but in the other one (and in the code challenge) he uses /$1/.

What is the difference between $ and % in a backreference?

1 Answer

Bob Hensley
Bob Hensley
26,781 Points

Both are backreferences, but for different sources. The dollar sign ($1-9) refers to RewriteRule. And the percentage sign (%1-9) refers to RewriteCond. It's just mod_rewrite's way of removing confusion about what the backreference is meant to actually reference.

Adam Zuckerberg
Adam Zuckerberg
22,248 Points

Thank you!