c# - How to encode a path that contains a hash?

Question

How do you properly encode a path that includes a hash (#) in it? Note the hash is not the fragment (bookmark?) indicator but part of the path name.

For example, if there is a path like this:

http://www.contoso.com/code/c#/somecode.cs

It causes problems when you for example try do this:

Uri myUri = new Uri("http://www.contoso.com/code/c#/somecode.cs");

It would seem that it interprets the hash as the fragment indicator.

It feels wrong to manually replace # with %23. Are there other characters that should be replaced? There are some escaping methods in Uri and HttpUtility but none seem to do the trick.

Answer 1

There are a few characters you are not supposed to use. You can try to work your way through this very dry documentation, or refer to this handy URL summary on Stack Overflow.

If you check out this very website, you'll see that their C# questions are encoded %23.

Stack Overflow C# Questions

You can do this using either (for ASP.NET):

string.Format("http://www.contoso.com/code/{0}/somecode.cs", 
    Server.UrlEncode("c#")
);

Or for class libraries / desktop:

string.Format("http://www.contoso.com/code/{0}/somecode.cs",
    HttpUtility.UrlEncode("c#")
);