Mapping Header cookie string to CookieCollection and vice versa

Consider a web response with this header:

Set-Cookie: sample=testCookie; Domain=.sample.com; Expires=Tue, 25-Jan-2012 00:49:29 GMT; Path=/

this header would be mapped to CookieCollection in .NET. And also when we deal with a CookieCollection it will finally converted to such a header string.

I'm looking some way to purely do this conversions in two way. Surely .NET has it in it's internal library. I believe any class which constructs object model from text and vice versa should support two methods (here CookieCollection):

// Creating cookie collection from header text
CookieCollection.TryParse(cookieHeaderString, out myCookieCollection);
// and getting the final header which would be sent by request
String cookieHeaderString = myCookieCollection.GetCookieHeaderString();

How can I achieve that with CookieCollection ?