1、获得当前运行程序的路径
string rootPath = Directory.GetCurrentDirectory();
2、获得该文件夹下的文件，返回类型为FileInfo

string path=@"X:\XXX\XX";
DirectoryInfo root = new DirectoryInfo(path);
FileInfo[] files=root.GetFiles();

3、获得该文件夹下的子目录，返回类型为DirectoryInfo

string path=@"X:\XXX\XX";
DirectoryInfo root = new DirectoryInfo(path);
DirctoryInfo[] dics=root.GetDirectories();

4、获得文件夹名

string path=@"X:\XXX\XX";
DirectoryInfo root = new DirectoryInfo(path);
string dicName=root.Name;

5、获得文件夹完整的路径名

string path=@"X:\XXX\XX";
DirectoryInfo root = new DirectoryInfo(path);
string dicName=root.FullName;

6、获取文件的Name和FullName

string path=@"X:\XXX\XX";
DirectoryInfo root = new DirectoryInfo(path);
foreach (FileInfo f in root.GetFiles())
{
    string name=f.Name;
    string fullName=f.FullName;
}

只获取目录下一级的文件夹与文件

String path = @"X:\xxx\xxx";

//第一种方法
string[] files = Directory.GetFiles(path, "*.txt");

foreach (string file in files)
{
    Console.WriteLine(file);
}

//第二种方法
DirectoryInfo folder = new DirectoryInfo(path);

foreach (FileInfo file in folder.GetFiles("*.txt"))
{
    Console.WriteLine(file.FullName);
}

递归地输出当前运行程序所在的磁盘下的所有文件名和子目录名

static void Main(string[] args)
        {
            //获取当前程序所在的文件路径
            String rootPath = Directory.GetCurrentDirectory();
            string parentPath = Directory.GetParent(rootPath).FullName;//上级目录
            string topPath = Directory.GetParent(parentPath).FullName;//上上级目录
            StreamWriter sw = null;
            try
            {
                //创建输出流，将得到文件名子目录名保存到txt中
                sw = new StreamWriter(new FileStream("fileList.txt", FileMode.Append));
                sw.WriteLine("根目录：" + topPath);
                getDirectory(sw, topPath, 2);
            }
            catch (IOException e)
            {
                Console.WriteLine(e.Message);
            }
            finally
            {
                if (sw != null)
                {
                    sw.Close();
                    Console.WriteLine("完成");
                }
            }

        }

        /// <summary>
        /// 获得指定路径下所有文件名
        /// </summary>
        /// <param name="sw">文件写入流</param>
        /// <param name="path">文件写入流</param>
        /// <param name="indent">输出时的缩进量</param>
        public static void getFileName(StreamWriter sw, string path, int indent)
        {
            DirectoryInfo root = new DirectoryInfo(path);
            foreach (FileInfo f in root.GetFiles())
            {
                for (int i = 0; i < indent; i++)
                {
                    sw.Write("  ");
                }
                sw.WriteLine(f.Name);
            }
        }

        /// <summary>
        /// 获得指定路径下所有子目录名
        /// </summary>
        /// <param name="sw">文件写入流</param>
        /// <param name="path">文件夹路径</param>
        /// <param name="indent">输出时的缩进量</param>
        public static void getDirectory(StreamWriter sw, string path, int indent)
        {
            getFileName(sw, path, indent);
            DirectoryInfo root = new DirectoryInfo(path);
            foreach (DirectoryInfo d in root.GetDirectories())
            {
                for (int i = 0; i < indent; i++)
                {
                    sw.Write("  ");
                }
                sw.WriteLine("文件夹：" + d.Name);
                getDirectory(sw, d.FullName, indent + 2);
                sw.WriteLine();
            }
        }

OK，结束！