Get host domain from URL?

Question

You can use Request object or Uri object to get host of url.

Using Request.Url

string host = Request.Url.Host;

Using Uri

Uri myUri = new Uri("http://www.contoso.com:8080/");   
string host = myUri.Host;  // host is "www.contoso.com"

Try like this;

Uri.GetLeftPart( UriPartial.Authority )

Defines the parts of a URI for the Uri.GetLeftPart method.

---

http://www.contoso.com/index.htm?date=today --> http://www.contoso.com

http://www.contoso.com/index.htm#main --> http://www.contoso.com

nntp://news.contoso.com/[email protected] --> nntp://news.contoso.com

file://server/filename.ext --> file://server

Uri uriAddress = new Uri("http://www.contoso.com/index.htm#search");
Console.WriteLine("The path of this Uri is {0}", uriAddress.GetLeftPart(UriPartial.Authority));

Demo

Use Uri class and use Host property

Uri url = new Uri(@"http://support.domain.com/default.aspx?id=12345");
Console.WriteLine(url.Host);

try following statement

 Uri myuri = new Uri(System.Web.HttpContext.Current.Request.Url.AbsoluteUri);
 string pathQuery = myuri.PathAndQuery;
 string hostName = myuri.ToString().Replace(pathQuery , "");

Example1

 Input : http://localhost:4366/Default.aspx?id=notlogin
 Ouput : http://localhost:4366

Example2

 Input : http://support.domain.com/default.aspx?id=12345
 Output: support.domain.com

The best way, and the right way to do it is using Uri.Authority field

Load and use Uri like so :

Uri NewUri;

if (Uri.TryCreate([string with your Url], UriKind.Absolute, out NewUri))
{
     Console.Writeline(NewUri.Authority);
}

Input : http://support.domain.com/default.aspx?id=12345
Output : support.domain.com

Input : http://www.domain.com/default.aspx?id=12345
output : www.domain.com

Input : http://localhost/default.aspx?id=12345
Output : localhost

If you want to manipulate Url, using Uri object is the good way to do it. https://msdn.microsoft.com/en-us/library/system.uri(v=vs.110).aspx

 var url = Regex.Match(url, @"(http:|https:)\/\/(.*?)\/");

INPUT = "https://stackoverflow.com/questions/";

OUTPUT = "https://stackoverflow.com/";