htaccess code for forwarding a domain

Issue :

The old domain ( with and without ‘www’ ) needs to be forwarded to a sub-folder of the new domain.

Solution :

Use the following htaccess code :

RewriteEngine on
RewriteCond %{HTTP_HOST} ^olddomain.com$ [OR]
RewriteCond %{HTTP_HOST} ^www.olddomain.com$
RewriteRule ^(.*)$ http://newdomain.com/folder/$1 [R=permanent,R]