Today I discovered a totally unexpected behavior when the .htaccess RewriteRule passes an encoded plus sign (%2B) to a query string. For example if you take and urlencode the URI "/foo/widget 2+.html" you get "/foo/widget+2%2B.html". Now take this URI and pass it to a querystring via the following RewriteRule:
RewriteRule ^(foo|bla|ick)/(.*)\.html$ /index.php?$1=$2 [L,QSA]
Now in index.php take and decode the variable $foo using the urldecode function:
What would the result be?
If you said "widget 2+" you would be wrong. What you end up with is "widget 2 " where the plus sign ends up being another space.
In order to get the plus sign back you would need to do the following:
Apparently, best I can tell when the RewriteRule passes %2B to a variable it converts the %2B back into a plus sign and then urldecode() converts the plus sign into a space.
I wasted half the morning figuring that one out.
So the next time you need to stump the chump at some get together of Apache gurus ask them the above scenario and see if they get it right. Odds are they won't.