1、安装命令工具

sudo apt-get -y install tree

2、可以查看关于tree命令的帮助信息

$ tree --help

usage: tree [-adfghilnpqrstuvxACDFNS] [-H baseHREF] [-T title ] [-L level [-R]]

        [-P pattern] [-I pattern] [-o filename] [--version] [--help] [--inodes]

        [--device] [--noreport] [--nolinks] [--dirsfirst] [--charset charset]

        [--filelimit #] [<directory list>]

  -a            All files are listed.

  -d            List directories only.

  -l            Follow symbolic links like directories.

  -f            Print the full path prefix for each file.

  -i            Don't print indentation lines.

  -q            Print non-printable characters as '?'.

  -N            Print non-printable characters as is.

  -p            Print the protections for each file.

  -u            Displays file owner or UID number.

  -g            Displays file group owner or GID number.

  -s            Print the size in bytes of each file.

  -h            Print the size in a more human readable way.

  -D            Print the date of last modification.

  -F            Appends '/', '=', '*', or '|' as per ls -F.

  -v            Sort files alphanumerically by version.

  -r            Sort files in reverse alphanumeric order.

  -t            Sort files by last modification time.

  -x            Stay on current filesystem only.

  -L level      Descend only level directories deep.

3、使用方法（常用）

(1) 显示当前目录的树形结构

jianbao@jianbao-pc:/www/软件开发$ tree

.

├── PPT

│   └── PHP性能监控与优化.pptx

├── 电子书

│   ├── Linux.环境C程序设计.徐诚.扫描版.pdf

│   └── UNIX环境高级编程（中文第三版）_扫描版.pdf

├── 视频

│   └── PHP_C扩展

│       ├── PHP扩展开发教程.mp4

│       ├── swoole第三节第4部分.mp4

│       ├── swoole视频教程第3节 swoole服务器的进程_线程模型.mp4

│       └── 其他

│           ├── swoole-chat第二节第二部分.mp4

│           ├── swoole-chat第二节第三部分.mp4

└── 手册

    └── php_enhanced_zh.chm

(2) 只查看当前第一级的目录和文件

$ tree -L 1

(3) 只查看当前第二级的目录和文件

$ tree -L 2

(4) 只查看当前第N级的目录和文件

$ tree -L N

(5) 把目录结构信息保存到文本中

$ tree -L 2 > /home/php-note.com/tree.txt