Question

I am trying to pass a Uri of new Uri(".example.com")

Invalid URI: The format of the URI could not be determined.

or new Uri("http://.example.com")

Invalid URI: The hostname could not be parsed.

I need to be able to use the CookieContainer.SetCookies function which only has one overload taking a Uri.

According to this page, .NET 4.0 should support dot prefixed cookies now, but it seems the Uri class does not?

Answer 1

In this case, you need to pass a proper uri to the function, and the Uri parser is correctly rejecting the malformed string you are trying to use.

I would advise using the Cookie Constructor that takes 4 parameters – allowing you to set the domain to a dot-prefixed one.

Cookie(string name, string value, string path, string domain);