Subdomains - How to create subdomains on the fly using code, which points to same website (root)

Hi,

In my application, I have a requirement as below,

1. for each user I have to create a subdomain.

2. Each subdomain will points to Root web site, I mean for user 'XYZ'. I should provide subdomain like 'xyz.mywebsite.com'.

3. 'xyz.mywebsite.com' - is points to root, (www.mywebsite.com). If I get subdomin request to webserver,I can convert sudomin to query string etc.....

 I am looking for a solutions like,

'To create subdomains based on user id on the fly from code, which will point to root website.'

 Please let me know your ideas & views on this.

Thank you,

Sreedhar Nasum.
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