I am using Ubuntu linux 8.10

I have installed Apache, PHP and MySQL on my pc and testing all scripts on my localhost by http://localhost/ .

Currently I am creating directories for each web projects to test on my localhost. So my project can be access by http://localhost/project01/ and so on.
http://localhost/project01 will access /var/www/project01
http://localhost/project02 will access /var/www/project02

There is some problems with server path in coding. When I would use file copy/paste process on my localhost, it requre path from root to work. And the path is different on my localhost and on sever.

So I think to use different domain name for different projects.
Example :
http://project01/ will access /var/www/project01
http://project02/ will access /var/www/project02

... or any other solution will be also welcome, so my localhost files and servers files are perfectly same.

Any guide for this?
Thank you.

if you are okay with the apache name based vhost config (see end of the default httpd.conf for an example)

The name resolution (so your server knows its got other names) is also fairly simple.

You can add the extra names to your /etc/host file. This is generally used to find names for servers before DNS is touched (which is configurable) so you can use the same technique for testing actual domains locally if required.