using (SPSite site = new SPSite(""))            {                using (SPWeb web = site.RootWeb)                {                    SPList list = web.Lists[""];                    SPFolder folder = list.RootFolder.SubFolders[""];                    SPFile file = folder.Files[0];                    file.Delete();                    file.Update();                }            }

 spsite["操作站点"]

web.Lists["操作列表"];