Running a C# program w/GUI through a web browser

Hi,

I have many thousand lines of C# code that uses System.Windows.*
frequently,
so it has a lot of GUI. This program processes data that is located on the
local machine and displays a graphical representation of this. I wish for
users to be able to use this program through the internet, where the
machine
containing the data is the server.

The code that processes the data and the code that displays the graphical
interface is already written, but as a single program. Is there an easy
way of getting the client-server functionality without splitting the
program
or writing too much code? Eg. executing the program through a web browser.

Thanks,
Magnus Gran-Jansen