Hey i'm curious as to how to parse out the host name in a URL using regular expressions in C#.
i have the following regex:
Regex regexUrl = new Regex("://(?<host>([a-z\\d][-a-z\\d]*[a-z\\d]\\.)*[a-z][-a-z\\d]+[a-z])");
but it throws an error when the URL does not contain a "http://", and it also does not parse out the "www." part of the url.
So how would i code a function that parses out the "hostname.com" from a URL, even if it does not contain a "http://". Thanks :)
I wouldn't use regular expressions.
Why not do somethiing like this instead?
Uri uri;
if (!Uri.TryCreate(s, UriKind.Absolute, out uri)) {
if (!Uri.TryCreate("http://" + s, UriKind.Absolute, out uri)) {
throw new ArgumentException();
}
}
return uri.Host;
It's more lines but it's probably cleaner than a regex and easier to read.
If you insist on using a regex this should do: ^([a-z]+://)?(?<host>[a-z\d][a-z\d-]*(\.[a-z\d][a-z\d-]*)*)[/$]
The trick is to have the last character match either a / or the terminator ($)
[^\/\.\s]+\.[^\/\.\s]+\/ - the only problem is that it requires / after hostname
