www 和非 www 重定向

將任何裸域重定向到 www.[your_domain].tld：

# Start Apache Rewriting engine
RewriteEngine On
# Make sure you're not already using www subdomain
# and that the host string is not empty
RewriteCond %{HTTP_HOST} !^$
RewriteCond %{HTTP_HOST} !^www\.
# We check for http/https connection protocol
RewriteCond %{HTTPS}s ^on(s)|
# In case the previous conditions matches, redirect to www
RewriteRule ^(.*)$ http%1://www.%{HTTP_HOST}/$1 [R=301,L]

將 www.[your_domain].tld 重定向到 [your_domain].tld

# Start Apache Rewriting engine
RewriteEngine On
# We check if we're on the www subdomain
RewriteCond %{HTTP_HOST} ^www\.([^\.]+\.[^\.]+)$
# In case the previous condition matches, redirect to non-www
RewriteRule ^(.*)$ http://%1/$1 [R=301,L]

將任何級別的巢狀子域重定向到你的主域：

# Start Apache Rewriting engine
RewriteEngine On
# We check if there's a subdomain
RewriteCond %{HTTP_HOST} \.([^.]+\.[^.]+)$
# redirect to the main domain name
RewriteRule ^ http://%1%{REQUEST_URI} [R=301,L]