I have two environment variables in apache config, I want to concatenate them into one new environment variable. Is this possible?
I realise this doesn't work, but it demonstrates the sort of thing I'm after:
SetEnv one foo
SetEnv two bar
SetEnv three one+two
...and then 'three' would have the value "foobar"
Use a mod_rewrite regular expression with two wildcard backreferences to access the environment variables and concatenate the strings:
#This will be true for any user agent
RewriteCond %{HTTP_USER_AGENT} ^.*
#Replace / with / and set the new environment variable
RewriteRule /(%{ENV:one})*(%{ENV:two})* / [E=three:$1$2]
来源:https://stackoverflow.com/questions/9397090/can-i-concatenate-environment-variables-in-apache-config