如何管理分类网站中的多个城市？

I am working on classified site. I am using PHP and MySql for that.

On my site when user select their city that time i want to change website url like in subdomain style. foreg:-

http://cityname.mywebsitename.com

Only one thing in my mind to implement this is creating sub domains for all cities. But it would be more difficult to manage when your cities goes 50+. You can't upload again and again same script for multiple domains. I think this is not a good idea to do this. I want to use a single script for that so i can manage it in simple way.

If you have any idea than please share..

Thanks in advance

I say you how i made it:

1. in DNS add wildcard subdomain record

   *.domain.tld. IN A 1.2.3.4

2. add wildcard virtualhost

   <VirtualHost 1.2.3.4>
   DocumentRoot /var/www/vhosts/wildcard
   ServerAlias *.domain.tld.
   ServerName domain.tld
   ...
   </VirtualHost >
   

3. create a .htaccess that redirect all requests to a FrontController (usually index.php)

   RewriteBase /
   RewriteCond %{REQUEST_FILENAME} !-f
   RewriteCond %{REQUEST_FILENAME} !-d
   RewriteRule . /index.php [L]
   

4. parse $_SERVER['HTTP_HOST'] from php to obtain city name and play with your new FrontController (usually index.php)

i've done it on dedicated server or VPS with linux and plesk. With some modifications on the previous basis points, it is possible everywhere;)

You can't upload again and again same script for multiple domains.

You wouldn't need to. A single web-server can support multiple domains, and files can be shared between them. See, for example, Apache's examples of setting up "virtual hosts".

Just setup a DNS wildcard so that they all go to the same site. Then using PHP you can figure out what subdomain is currently being used. Also just make sure that they all use a SESSION or COOKIE based on the domain not the subdomain if you want information to be accessible between them all.

You will also need to setup apache to accept the wildcard. So that all subdomains get directed to the same code.

$urlParts = explode('.', $_SERVER['HTTP_HOST']);
$subdomain = $urlParts[0];

Don't go the path of using Apache Virtual Hosts... While you could store scripts in a common folder and access them all via PHP (include('../common_scripts/file.php') you still have to manage the vhost configuration. Better to set up a DNS wildcard and then have a single site which takes into account the current URL when running queries.