Remove last segment of Request.Url

Question

I would like to remove the last segment of Request.Url, so for instance...

http://www.example.com/admin/users.aspx/deleteUser

Answer 1

To remove the last segment of Request.Url it is enough to subtract from absolute uri the length of last segment.

string uriWithoutLastSegment = Request.Url.AbsoluteUri.Remove(
  Request.Url.AbsoluteUri.Length - Request.Url.Segments.Last().Length );

Answer 2

Use the Uri class to parse the URI - you can access all the segments using the Segments property and rebuild the URI without the last segment.

var uri = new Uri(myString);

var noLastSegment = string.Format("{0}://{1}", uri.Scheme, uri.Authority);

for(int i = 0; i < uri.Segments.Length - 1; i++)
{
   noLastSegment += uri.Segments[i];
}

noLastSegment = noLastSegment.Trim("/".ToCharArray()); // remove trailing `/`

As an alternative to getting the scheme and host name, as suggested by Dour High Arch in his comment:

var noLastSegment = uri.GetComponents(UriComponents.SchemeAndServer, 
                                      UriFormat.SafeUnescaped);

Answer 3

Much the same as @Oded's answer, but using a UriBuilder instead:

var uri = new Uri("http://www.example.com/admin/users.aspx/deleteUser");
var newSegments = uri.Segments.Take(uri.Segments.Length - 1).ToArray();
newSegments[newSegments.Length-1] = 
    newSegments[newSegments.Length-1].TrimEnd('/');
var ub=new UriBuilder(uri);
ub.Path=string.Concat(newSegments);
//ub.Query=string.Empty;  //maybe?
var newUri=ub.Uri;

Answer 4

I find manipulating Uri's fairly annoying, and as the other answers are quite verbose, here's my two cents in the form of an extension method.

As a bonus you also get a replace last segement method. Both methods will leave querystring and other parts of the url intact.

public static class UriExtensions
{
    private static readonly Regex LastSegmentPattern = 
        new Regex(@"([^:]+://[^?]+)(/[^/?#]+)(.*$)", RegexOptions.Compiled | RegexOptions.IgnoreCase);        

    public static Uri ReplaceLastSegement(this Uri me, string replacement)
        => me != null ? new Uri(LastSegmentPattern.Replace(me.AbsoluteUri, $"$1/{replacement}$3")) : null;

    public static Uri RemoveLastSegement(this Uri me)
        => me != null ? new Uri(LastSegmentPattern.Replace(me.AbsoluteUri, "$1$3")) : null;
}

Answer 5

Well the trivial solution would be to iterate char by char from the end of the string towards its beginning and search for the first '/' to come (I guess that also came into your mind).

Try this:

string url = "http://www.example.com/admin/users.aspx/deleteUser";

for (int i = url.Length - 1; i >= 0; i--) {

    if (url[i] == '/') return url.Substring(0, i - 1);
}