Question

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 🙂

Answer 1

I wouldn’t use regular expressions.

1. Convert ‘http://’ to ” (empty string) in your string – that basically removes http:// if it’s there
2. Split the string on / as an array
3. The hostname is the element at index 0