What is the folders name that default.cs is located in

 Hi,
 
I have created a Folder and inside this folder, I have put a default.aspx and a default.cs file.
I wonder how it is possible to find out what is the folders name as the default.cs is located in. This meens that I am looking for a code to determine what folder that is above in the hierarchy of folders ?
I cant use this code as this goes all the way back to the root:
Server.MapPath("~/");
 
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