Regexp to find the subdomain (if any) from $HTTP_HOST

[Leif Wessman]

I need help creating a regular expression to find the subdomain in the
$HTTP_HOST variable.

The domain is always in this form:

https://www.domain.com

or
uk.domain.com
or
domain.com

there is no such thing as a
sub.sub.sub.dom ain.com
(not in my case, at least)

So, I need to find out if the subdomain is empty, "www" or "uk".

Can someone help me?

Leif

[Martin C. Petersen]

Re: Regexp to find the subdomain (if any) from $HTTP_HOST

> I need help creating a regular expression to find the subdomain in the[color=blue]
> $HTTP_HOST variable.[/color]
No need for regular expressions in this case:
<?php
$parts = explode(".",$HT TP_HOST);
$length = count($parts);
$subdomain = $length>2 ? $parts[$length-3] : "";
?>


Martin

[Shawn Wilson]

Re: Regexp to find the subdomain (if any) from $HTTP_HOST

Leif Wessman wrote:[color=blue]
>
> I need help creating a regular expression to find the subdomain in the
> $HTTP_HOST variable.
>
> The domain is always in this form:
>
> www.domain.com
> or
> uk.domain.com
> or
> domain.com
>
> there is no such thing as a
> sub.sub.sub.dom ain.com
> (not in my case, at least)
>
> So, I need to find out if the subdomain is empty, "www" or "uk".
>
> Can someone help me?
>
> Leif[/color]

Untested:

$foo = preg_replace("/^(http:\/\/)?([^\.]+)?(\.?domain\. com.*)$", "\$2",
$HTTP_HOST);
switch($foo) {
case "www":
//statements
break;
case "uk":
//statements
break;
case "":
//statements
break;
default:
echo "Unrecoginz ed URL";
}
--
Shawn Wilson
shawn@glassgian t.com

http://www.glassgiant.com