c# 获取项目的根路径

//获取.exe文件路径
string currentPath = Application.StartupPath;

//获取该文件的上级路径
Directory.SetCurrentDirectory(Directory.GetParent(Directory.GetCurrentDirectory()).FullName);
string parentPath=Directory.GetCurrentDirectory();

//如果需要继续上级路径，继续执行，就可以得到两次的上级路径
Directory.SetCurrentDirectory(Directory.GetParent(Directory.GetCurrentDirectory()).FullName);