Searching URL String for Subdomain value - DOTNET

hi,
you should use regular expressions for this job, they are in their element
here.
you can use the expression [\w-]+ to match all the components of a URL.
for example, running Regex.Matches on http://joe.mysite.com will yield 4
captures in the first group:
http joe mysite com
you can then decide how you want to deal with them. you want to support
someone using HTTPS, and also a domain without a subdomain, such as
http://mysite.com or even http://mysite if running in an intranet
environment.
plenty of regex tutorials on the net and in the SDK docs if you need a
refresher on regex.
good luck
tim

"CSINVA" <mcse_instructor@yahoo.com> wrote in message
news:1193880562.557651.135010@v3g2000hsg.googlegroups.com...
>I have my DNS setup to answer for any subdomain. I need to be able to
> look at the URL typed in like "joe.mysite.com" and put the subdomain
> in a variable, so I can then look it up in a database. This would have
> to work if they typed in http://joe.mysite.com or just joe.mysite.com.
>
> Here is what I have started with, but as you can see I'm a little
> stuck.
>
> Sub ExtractDomain(ByVal expr As String)
>
> Dim sURL As String = Page.Request.Url.ToString()
> Dim subDomain = InStr(1, sURL, "http://")
> If subDomain > 0 Then
> 'True so count over 7 characters
>
>
> Else
> 'False, so start immediately
>
>
> End If
>
> End Sub
>

"CSINVA" <mcse_instructor@yahoo.com> wrote in message
news:1193880562.557651.135010@v3g2000hsg.googlegroups.com...
>I have my DNS setup to answer for any subdomain. I need to be able to
> look at the URL typed in like "joe.mysite.com" and put the subdomain
> in a variable, so I can then look it up in a database. This would have
> to work if they typed in http://joe.mysite.com or just joe.mysite.com.
>

Use System.Uri and the TryCreate method, then check the Host property.