class Program

    {

        static void Main(string[] args)

        {

            //获取当前运行程序的目录

            string fileDir = Environment.CurrentDirectory;

            Console.WriteLine("当前程序目录："+fileDir);

            //一个文件目录

            string filePath = "C:\\JiYF\\BenXH\\BenXHCMS.xml";

            Console.WriteLine("该文件的目录："+filePath);

            string str = "获取文件的全路径：" + Path.GetFullPath(filePath); //-->C:\JiYF\BenXH\BenXHCMS.xml

            Console.WriteLine(str);

            str = "获取文件所在的目录：" + Path.GetDirectoryName(filePath); //-->C:\JiYF\BenXH

            Console.WriteLine(str);

            str = "获取文件的名称含有后缀：" + Path.GetFileName(filePath); //-->BenXHCMS.xml

            Console.WriteLine(str);

            str = "获取文件的名称没有后缀：" + Path.GetFileNameWithoutExtension(filePath); //-->BenXHCMS

            Console.WriteLine(str);

            str = "获取路径的后缀扩展名称：" + Path.GetExtension(filePath); //-->.xml

            Console.WriteLine(str);

            str = "获取路径的根目录：" + Path.GetPathRoot(filePath); //-->C:\

            Console.WriteLine(str);

            Console.ReadKey();

        }

    }

参考资料：https://www.cnblogs.com/JiYF/p/6879139.html