Remove characters after specific character in string, then remove substring?

Question

I feel kind of dumb posting this when this seems kind of simple and there are tons of questions on strings/characters/regex, but I couldn't find quite what I needed (except in another language: http://stackoverflow.com/questions/2176544/remove-all-text-after-certain-point).

I've got the following code:

[Test]
    public void stringManipulation()
    {
        String filename = "testpage.aspx";
        String currentFullUrl = "http://localhost:2000/somefolder/myrep/test.aspx?q=qvalue";
        String fullUrlWithoutQueryString = currentFullUrl.Replace("?.*", "");
        String urlWithoutPageName = fullUrlWithoutQueryString.Remove(fullUrlWithoutQueryString.Length - filename.Length);

        String expected = "http://localhost:2000/somefolder/myrep/";
        String actual = urlWithoutPageName;
        Assert.AreEqual(expected, actual);
    }

I tried the solution in the question above (hoping the syntax would be the same!) but nope. I want to first remove the queryString which could be any variable length, then remove the page name, which again could be any length.

How can I get the remove the query string from the full URL such that this test passes?

Answer 1

For string manipulation, if you just want to kill everything after the ?, you can do this

string input = "http://www.somesite.com/somepage.aspx?whatever";
int index = input.IndexOf("?");
if (index > 0)
   input = input.Substring(0, index);

Edit: If everything after the last slash, do something like

string input = "http://www.somesite.com/somepage.aspx?whatever";
int index = input.LastIndexOf("/");
if (index > 0)
    input = input.Substring(0, index); // or index + 1 to keep slash

Alternately, since you're working with a URL, you can do something with it like this code

System.Uri uri = new Uri("http://www.somesite.com/what/test.aspx?hello=1");
string fixedUri = uri.AbsoluteUri.Replace(uri.Query, string.Empty);

Answer 2

The Uri class is generally your best bet for manipulating Urls.

Answer 3

I second Hightechrider: there is a specialized Url class already built for you.

I must also point out, however, that the PHP's replaceAll uses regular expressions for search pattern, which you can do in .NET as well - look at the RegEx class.