【批处理DOS-CMD命令-汇总和小结】-外部命令-cmd下载命令、抓包命令（wget）

一、wget下载程序的优势

1）支持断点下传功能

2）同时支持FTP和HTTP下载方式

3）支持代理服务器

4）设置方便简单

5）程序小，完全免费

二、下载和安装wget程序

wget的官网如下：Wget for Windows

不过很奇怪的是， 所有的下载链接，都出现了301错误。

于是我不得不换一个网站下载，推荐网站GNU Wget 1.21.3 for Windows

我下载了1.21.3 的64位版本zip文件包。 

解压后，将这个文件夹整体移动到c盘下的system32目录下，配置环境变量，即安装完成。

三、wget命令的使用方法

 

3.1 wget命令的帮助信息——wget --help

如果你执行这个命令是正常的，那么就说明安装成功，如果报错——wget既不是内部命令也不是外部命令，那么说明安装失败了。

往往是你环境变量的配置有问题。

C:\Users\Administrator>wget --help
GNU Wget 1.21.3, a non-interactive network retriever.
Usage: wget [OPTION]... [URL]...

Mandatory arguments to long options are mandatory for short options too.

Startup:
  -V,  --version                   display the version of Wget and exit
  -h,  --help                      print this help
  -b,  --background                go to background after startup
  -e,  --execute=COMMAND           execute a `.wgetrc'-style command

Logging and input file:
  -o,  --output-file=FILE          log messages to FILE
  -a,  --append-output=FILE        append messages to FILE
  -d,  --debug                     print lots of debugging information
  -q,  --quiet                     quiet (no output)
  -v,  --verbose                   be verbose (this is the default)
  -nv, --no-verbose                turn off verboseness, without being quiet
       --report-speed=TYPE         output bandwidth as TYPE.  TYPE can be bits
  -i,  --input-file=FILE           download URLs found in local or external FILE
       --input-metalink=FILE       download files covered in local Metalink FILE
  -F,  --force-html                treat input file as HTML
  -B,  --base=URL                  resolves HTML input-file links (-i -F)
                                     relative to URL
       --config=FILE               specify config file to use
       --no-config                 do not read any config file
       --rejected-log=FILE         log reasons for URL rejection to FILE

Download:
  -t,  --tries=NUMBER              set number of retries to NUMBER (0 unlimits)
       --retry-connrefused         retry even if connection is refused
       --retry-on-http-error=ERRORS    comma-separated list of HTTP errors to retry
  -O,  --output-document=FILE      write documents to FILE
  -nc, --no-clobber                skip downloads that would download to
                                     existing files (overwriting them)
       --no-netrc                  don't try to obtain credentials from .netrc
  -c,  --continue                  resume getting a partially-downloaded file
       --start-pos=OFFSET          start downloading from zero-based position OFFSET
       --progress=TYPE             select progress gauge type
       --show-progress             display the progress bar in any verbosity mode
  -N,  --timestamping              don't re-retrieve files unless newer than
                                     local
       --no-if-modified-since      don't use conditional if-modified-since get
                                     requests in timestamping mode
       --no-use-server-timestamps  don't set the local file's timestamp by
                                     the one on the server
  -S,  --server-response           print server response
       --spider                    don't download anything
  -T,  --timeout=SECONDS           set all timeout values to SECONDS
       --dns-servers=ADDRESSES     list of DNS servers to query (comma separated)
       --bind-dns-address=ADDRESS  bind DNS resolver to ADDRESS (hostname or IP) on local host
       --dns-timeout=SECS          set the DNS lookup timeout to SECS
       --connect-timeout=SECS      set the connect timeout to SECS
       --read-timeout=SECS         set the read timeout to SECS
  -w,  --wait=SECONDS              wait SECONDS between retrievals
                                     (applies if more then 1 URL is to be retrieved)
       --waitretry=SECONDS         wait 1..SECONDS between retries of a retrieval
                                     (applies if more then 1 URL is to be retrieved)
       --random-wait               wait from 0.5*WAIT...1.5*WAIT secs between retrievals
                                     (applies if more then 1 URL is to be retrieved)
       --no-proxy                  explicitly turn off proxy
  -Q,  --quota=NUMBER              set retrieval quota to NUMBER
       --bind-address=ADDRESS      bind to ADDRESS (hostname or IP) on local host
       --limit-rate=RATE           limit download rate to RATE
       --no-dns-cache              disable caching DNS lookups
       --restrict-file-names=OS    restrict chars in file names to ones OS allows
       --ignore-case               ignore case when matching files/directories
  -4,  --inet4-only                connect only to IPv4 addresses
  -6,  --inet6-only                connect only to IPv6 addresses
       --prefer-family=FAMILY      connect first to addresses of specified family,
                                     one of IPv6, IPv4, or none
       --user=USER                 set both ftp and http user to USER
       --password=PASS             set both ftp and http password to PASS
       --ask-password              prompt for passwords
       --use-askpass=COMMAND       specify credential handler for requesting
                                     username and password.  If no COMMAND is
                                     specified the WGET_ASKPASS or the SSH_ASKPASS
                                     environment variable is used.
       --no-iri                    turn off IRI support
       --local-encoding=ENC        use ENC as the local encoding for IRIs
       --remote-encoding=ENC       use ENC as the default remote encoding
       --unlink                    remove file before clobber
       --keep-badhash              keep files with checksum mismatch (append .badhash)
       --metalink-index=NUMBER     Metalink application/metalink4+xml metaurl ordinal NUMBER
       --metalink-over-http        use Metalink metadata from HTTP response headers
       --preferred-location        preferred location for Metalink resources

Directories:
  -nd, --no-directories            don't create directories
  -x,  --force-directories         force creation of directories
  -nH, --no-host-directories       don't create host directories
       --protocol-directories      use protocol name in directories
  -P,  --directory-prefix=PREFIX   save files to PREFIX/..
       --cut-dirs=NUMBER           ignore NUMBER remote directory components

HTTP options:
       --http-user=USER            set http user to USER
       --http-password=PASS        set http password to PASS
       --no-cache                  disallow server-cached data
       --default-page=NAME         change the default page name (normally
                                     this is 'index.html'.)
  -E,  --adjust-extension          save HTML/CSS documents with proper extensions
       --ignore-length             ignore 'Content-Length' header field
       --header=STRING             insert STRING among the headers
       --compression=TYPE          choose compression, one of auto, gzip and none. (default: none)
       --max-redirect              maximum redirections allowed per page
       --proxy-user=USER           set USER as proxy username
       --proxy-password=PASS       set PASS as proxy password
       --referer=URL               include 'Referer: URL' header in HTTP request
       --save-headers              save the HTTP headers to file
  -U,  --user-agent=AGENT          identify as AGENT instead of Wget/VERSION
       --no-http-keep-alive        disable HTTP keep-alive (persistent connections)
       --no-cookies                don't use cookies
       --load-cookies=FILE         load cookies from FILE before session
       --save-cookies=FILE         save cookies to FILE after session
       --keep-session-cookies      load and save session (non-permanent) cookies
       --post-data=STRING          use the POST method; send STRING as the data
       --post-file=FILE            use the POST method; send contents of FILE
       --method=HTTPMethod         use method "HTTPMethod" in the request
       --body-data=STRING          send STRING as data. --method MUST be set
       --body-file=FILE            send contents of FILE. --method MUST be set
       --content-disposition       honor the Content-Disposition header when
                                     choosing local file names (EXPERIMENTAL)
       --content-on-error          output the received content on server errors
       --auth-no-challenge         send Basic HTTP authentication information
                                     without first waiting for the server's
                                     challenge

HTTPS (SSL/TLS) options:
       --secure-protocol=PR        choose secure protocol, one of auto, SSLv2,
                                     SSLv3, TLSv1, TLSv1_1, TLSv1_2, TLSv1_3 and PFS
       --https-only                only follow secure HTTPS links
       --no-check-certificate      don't validate the server's certificate
       --certificate=FILE          client certificate file
       --certificate-type=TYPE     client certificate type, PEM or DER
       --private-key=FILE          private key file
       --private-key-type=TYPE     private key type, PEM or DER
       --ca-certificate=FILE       file with the bundle of CAs
       --ca-directory=DIR          directory where hash list of CAs is stored
       --crl-file=FILE             file with bundle of CRLs
       --pinnedpubkey=FILE/HASHES  Public key (PEM/DER) file, or any number
                                   of base64 encoded sha256 hashes preceded by
                                   'sha256//' and separated by ';', to verify
                                   peer against
       --random-file=FILE          file with random data for seeding the SSL PRNG

       --ciphers=STR           Set the priority string (GnuTLS) or cipher list string (OpenSSL) directly.
                                   Use with care. This option overrides --secure-protocol.
                                   The format and syntax of this string depend on the specific SSL/TLS engine.
HSTS options:
       --no-hsts                   disable HSTS
       --hsts-file                 path of HSTS database (will override default)

FTP options:
       --ftp-user=USER             set ftp user to USER
       --ftp-password=PASS         set ftp password to PASS
       --no-remove-listing         don't remove '.listing' files
       --no-glob                   turn off FTP file name globbing
       --no-passive-ftp            disable the "passive" transfer mode
       --preserve-permissions      preserve remote file permissions
       --retr-symlinks             when recursing, get linked-to files (not dir)

FTPS options:
       --ftps-implicit                 use implicit FTPS (default port is 990)
       --ftps-resume-ssl               resume the SSL/TLS session started in the control connection when
                                         opening a data connection
       --ftps-clear-data-connection    cipher the control channel only; all the data will be in plaintext
       --ftps-fallback-to-ftp          fall back to FTP if FTPS is not supported in the target server
WARC options:
       --warc-file=FILENAME        save request/response data to a .warc.gz file
       --warc-header=STRING        insert STRING into the warcinfo record
       --warc-max-size=NUMBER      set maximum size of WARC files to NUMBER
       --warc-cdx                  write CDX index files
       --warc-dedup=FILENAME       do not store records listed in this CDX file
       --no-warc-compression       do not compress WARC files with GZIP
       --no-warc-digests           do not calculate SHA1 digests
       --no-warc-keep-log          do not store the log file in a WARC record
       --warc-tempdir=DIRECTORY    location for temporary files created by the
                                     WARC writer

Recursive download:
  -r,  --recursive                 specify recursive download
  -l,  --level=NUMBER              maximum recursion depth (inf or 0 for infinite)
       --delete-after              delete files locally after downloading them
  -k,  --convert-links             make links in downloaded HTML or CSS point to
                                     local files
       --convert-file-only         convert the file part of the URLs only (usually known as the basename)
       --backups=N                 before writing file X, rotate up to N backup files
  -K,  --backup-converted          before converting file X, back up as X.orig
  -m,  --mirror                    shortcut for -N -r -l inf --no-remove-listing
  -p,  --page-requisites           get all images, etc. needed to display HTML page
       --strict-comments           turn on strict (SGML) handling of HTML comments

Recursive accept/reject:
  -A,  --accept=LIST               comma-separated list of accepted extensions
  -R,  --reject=LIST               comma-separated list of rejected extensions
       --accept-regex=REGEX        regex matching accepted URLs
       --reject-regex=REGEX        regex matching rejected URLs
       --regex-type=TYPE           regex type (posix|pcre)
  -D,  --domains=LIST              comma-separated list of accepted domains
       --exclude-domains=LIST      comma-separated list of rejected domains
       --follow-ftp                follow FTP links from HTML documents
       --follow-tags=LIST          comma-separated list of followed HTML tags
       --ignore-tags=LIST          comma-separated list of ignored HTML tags
  -H,  --span-hosts                go to foreign hosts when recursive
  -L,  --relative                  follow relative links only
  -I,  --include-directories=LIST  list of allowed directories
       --trust-server-names        use the name specified by the redirection
                                     URL's last component
  -X,  --exclude-directories=LIST  list of excluded directories
  -np, --no-parent                 don't ascend to the parent directory

Email bug reports, questions, discussions to <[email protected]>
and/or open issues at https://savannah.gnu.org/bugs/?func=additem&group=wget.

 

3.2 wget命令的基本用法——wget site

假设我们要下载B站某个视频的封面图，我们可以执行命令【wget https://i2.hdslb.com/bfs/archive/[email protected]_378h_1c.webphttps://funimg.pddpic.com/ddjb/2020-09-16/804f5f88-82d4-4b3f-9cfe-06d4d172fec3.png.slim.pnghttps://i2.hdslb.com/bfs/archive/[email protected]_378h_1c.webp】。

 下载成功。

  在2345看图王中打开这个webp格式的图片，正常无误。

 注意：不是所有图片都支持用wget命令下载，比如谷歌的logo图片链接是https://www.google.com/images/branding/googlelogo/2x/googlelogo_color_92x30dp.png

，我们用wget命令下载的时候，发现服务器拒绝回应。

但是我们用浏览器直接访问这个链接，就是正常的。

刚刚下载的是图片，我们试一个视频【https://v26-web.douyinvod.com/0a9c9db510fa69375b8ca201d682aee5/62b59bc7/video/tos/cn/tos-cn-ve-15c001-alinc2/8d2c907ce7144fa8ad9fe39fff903e1b/?a=6383&ch=5&cr=0&dr=0&lr=all&cd=0%7C0%7C0%7C0&cv=1&br=3130&bt=3130&cs=0&ds=6&ft=5q_lc5mmnPKe2N4EqM9wTqdlYhd.YPjcTR3-&mime_type=video_mp4&qs=0&rc=Nmg5Ojc7NDU0NDVoaGk0PEBpM2Q5Njo6Zjs7ZDMzNGkzM0A0L2MvNGA2XjYxMV5hNDViYSM1bWlwcjQwcl5gLS1kLS9zcw%3D%3D&l=20220624181002010208016205390882DC】

成功下载。

下载得到的文件有待补充扩展名。

 补充扩展名后，打开，非常成功。 

最后，我们尝试下载一下网页，比如百度搜索首页，让我们执行命令【wget www.baidu.com】。

下载到当前目录后，让我们打开看看？还行达到预期了。

 

 3.3 下载日志输出至目标文件——参数-o（小写）

简版参数-o的长版是--output-file，因此假设我们想要下载百度搜索网页，那么我们可以执行命令【wget -o log.txt www.baidu.com】或者【wget --output-file=log.txt www.baidu.com】。

执行命令后，在当前目录下新增了一个日志文件、一个html文件，但是日志并没有显示在cmd窗口中了。

 

 

3.4  从文本文件中批量取出url——参数-i

简版参数-i的长版是--input-file，因此假设我们想要下载一个批量的资源，并且这些资源的url在一个文本文件中存储，那么我们可以执行命令【wget -i url.txt】或者【wget --input-file=url.txt】。

新建一个txt文件，里面包括了两行url。

执行命令 【wget -i url.txt】，成功下载。

 

3.5 下载并重命名——参数-O（大写）

从上面几个小节，我们容易得出“如果不主动给下载的资源文件命名，那么程序一般会自动加html扩展名或者不加”。

因此，为了省掉后续在资源管理器中重命名的麻烦，我们可以直接在执行下载命令时就做好这一操作。

简版参数-O的长版是--output-document，如果你想要下载并重命名，可以执行命令【wget -O filename url】或者【wget --output-document=filename url】。

执行命令【wget -O baidu.html www.baidu.com】。

如果你想存在指定目录，并且对文件重命名，那么你可以写成【wget -O filepath url】的形式，其中filepath中最后一段应该是一个文件名。  

可见，-O参数不仅可以重命名，也可以实现后面提到的参数-P的功能。

3.6 下载至指定文件夹——参数-P（大写）

简版参数-P的长版是--directory-prefix，因此假设我们将资源下载到指定文件夹，那么我们可以执行命令【wget -O directory url】或者【wget --directory-prefix=directory url】。

将下载的资源存到目录webpage（可以是未存在的目录）下，执行命令【wget -P webpage www.baidu.com】。

 

3.7 递归下载整个网站——参数-r

简版参数-r的长版是--recursive，因此假设我们想要下载对应网站的全部资源，那么我们可以执行命令【wget -r url】或者【wget --recursive url】。

不妨试试对CSDN的网站进行爬虫，因为下载的资源都会保存至以url命名的文件夹中，所以执行命令【wget -r www.csdn.net】后也不需担心各种文件下载后会和其他文件混乱。

执行完后，我们发现只下载了两个文件，其中有一个名称为robot.txt的文件，说明CSDN网站存在反爬虫的机制，毕竟是商业大站，我认怂...

我们试试爬一些小站，比如说北京某知名高校的官网（在这里温馨提示一下，不要乱搞，你如果没爬出问题还好，爬出问题来了，惹祸了，小心高校到时候给你发律师函，所以不要持续地爬，试试就行了）。

执行命令【wget -r www.tsinghua.edu.cn】，然后我们可以看到cmd窗口一直在滚动，说明这个网站没有反爬虫机制。

但是出于不想太“刑”的考量，我还是按下ctrl+c键停止了爬虫，下载到的资源文件如下图所示。

 

 

四、对Cmd命令的小结和反思

在上面用wget命令对参数-i进行实验时，我发现执行命令【wget -i=url.txt】会找不到文件。

而后，经过一段时间，我看了网上其他文章对这种参数有简版、也有长版形式的情况，参数值最好是与参数用空格隔开。

因为对于简版形式，参数和参数值不能用等号隔开，但是可以用空格隔开；而对于长版形式，参数和参数值之间可以用等号或者空格隔开。

如果采用了不合适的语法，就会导致参数值被错误地赋予给参数。

比如执行命令【wget -o=log.txt www.baidu.com】后，生成的日志文件名称不叫“log.txt”，而叫“=log.txt”。