Node.js process.env()用法及代码示例

process.argv() 方法用于获取用户环境对象。此对象将包含有关执行此命令的环境的所有信息。

用法

process.env()

参数

因为它为用户环境返回一个对象。它不需要用户的任何输入。

示例

创建一个名为 env.js 的文件并复制以下代码片段。创建文件后，使用以下命令运行此代码，如下例所示 -

node env.js

env.js

// Node.js program to demonstrate the use of process.env

// Importing the process module
const process = require('process');

// Printing the user environment object
console.log(process.env);

输出

admin@root:~/node/test$ node env.js
{ SHELL:'/bin/bash',
SESSION_MANAGER:
'local/admin:@/tmp/.ICE-unix/2956,unix/admin:/tmp/.ICE-unix/2956',
QT_ACCESSIBILITY:'1',
COLORTERM:'truecolor',
XDG_CONFIG_DIRS:'/etc/xdg/xdg-ubuntu:/etc/xdg',
XDG_MENU_PREFIX:'gnome-',
GNOME_DESKTOP_SESSION_ID:'this-is-deprecated',
LANGUAGE:'en_IN:en',
GNOME_SHELL_SESSION_MODE:'ubuntu',
SSH_AUTH_SOCK:'/run/user/1001/keyring/ssh',
XMODIFIERS:'@im=ibus',
DESKTOP_SESSION:'ubuntu',
SSH_AGENT_PID:'2912',
GTK_MODULES:'gail:atk-bridge',
PWD:'/home/admin/test',
LOGNAME:'admin',
XDG_SESSION_DESKTOP:'ubuntu',
XDG_SESSION_TYPE:'x11',
GPG_AGENT_INFO:'/run/user/1001/gnupg/S.gpg-agent:0:1',
XAUTHORITY:'/run/user/1001/gdm/Xauthority',
GJS_DEBUG_TOPICS:'JS ERROR;JS LOG',
WINDOWPATH:'2',
HOME:'/home/admin',
USERNAME:'admin',
IM_CONFIG_PHASE:'1',
LANG:'en_IN',
LS_COLORS:

'rs=0:di=01;34:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=40;31
;01:mi=00:su=37;41:sg=30;43:ca=30;41:tw=30;42:ow=34;42:st=37;44:ex=01;32:*.tar=01;31:*.tgz
=01;31:*.arc=01;31:*.arj=01;31:*.taz=01;31:*.lha=01;31:*.lz4=01;31:*.lzh=01;31:*.lzma=01;31:*.tl
z=01;31:*.txz=01;31:*.tzo=01;31:*.t7z=01;31:*.zip=01;31:*.z=01;31:*.dz=01;31:*.gz=01;31:*.lrz=0
1;31:*.lz=01;31:*.lzo=01;31:*.xz=01;31:*.zst=01;31:*.tzst=01;31:*.bz2=01;31:*.bz=01;31:*.tbz=01
;31:*.tbz2=01;31:*.tz=01;31:*.deb=01;31:*.rpm=01;31:*.jar=01;31:*.war=01;31:*.ear=01;31:*.sar=
01;31:*.rar=01;31:*.alz=01;31:*.ace=01;31:*.zoo=01;31:*.cpio=01;31:*.7z=01;31:*.rz=01;31:*.cab
=01;31:*.wim=01;31:*.swm=01;31:*.dwm=01;31:*.esd=01;31:*.jpg=01;35:*.jpeg=01;35:*.mjpg=01
;35:*.mjpeg=01;35:*.gif=01;35:*.bmp=01;35:*.pbm=01;35:*.pgm=01;35:*.ppm=01;35:*.tga=01;35:
*.xbm=01;35:*.xpm=01;35:*.tif=01;35:*.tiff=01;35:*.png=01;35:*.svg=01;35:*.svgz=01;35:*.mng=0
1;35:*.pcx=01;35:*.mov=01;35:*.mpg=01;35:*.mpeg=01;35:*.m2v=01;35:*.mkv=01;35:*.webm=0
1;35:*.ogm=01;35:*.mp4=01;35:*.m4v=01;35:*.mp4v=01;35:*.vob=01;35:*.qt=01;35:*.nuv=01;35:
*.wmv=01;35:*.asf=01;35:*.rm=01;35:*.rmvb=01;35:*.flc=01;35:*.avi=01;35:*.fli=01;35:*.flv=01;35
:*.gl=01;35:*.dl=01;35:*.xcf=01;35:*.xwd=01;35:*.yuv=01;35:*.cgm=01;35:*.emf=01;35:*.ogv=01;
35:*.ogx=01;35:*.aac=00;36:*.au=00;36:*.flac=00;36:*.m4a=00;36:*.mid=00;36:*.midi=00;36:*.mk
a=00;36:*.mp3=00;36:*.mpc=00;36:*.ogg=00;36:*.ra=00;36:*.wav=00;36:*.oga=00;36:*.opus=00;
36:*.spx=00;36:*.xspf=00;36:',
XDG_CURRENT_DESKTOP:'ubuntu:GNOME',
VTE_VERSION:'6003',
GNOME_TERMINAL_SCREEN:
'/org/gnome/Terminal/screen/82170ab9_b5b3_424d_b0ce_37a40eb4e264',
INVOCATION_ID:'9f9745f4c0c546eaa78b2c84f6d7ae59',
MANAGERPID:'2722',
GJS_DEBUG_Output:'stderr',
LESSCLOSE:'/usr/bin/lesspipe %s %s',
XDG_SESSION_CLASS:'user',
TERM:'xterm-256color',
LESSOPEN:'- /usr/bin/lesspipe %s',
USER:'admin',
GNOME_TERMINAL_SERVICE:':1.111',
DISPLAY:':0',
SHLVL:'1',
QT_IM_MODULE:'ibus',
XDG_RUNTIME_DIR:'/run/user/1001',
JOURNAL_STREAM:'9:66796',
XDG_DATA_DIRS:
'/usr/share/ubuntu:/usr/local/share/:/usr/share/:/var/lib/snapd/desktop',
PATH:
'/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin',
GDMSESSION:'ubuntu',
DBUS_SESSION_BUS_ADDRESS:'unix:path=/run/user/1001/bus',
_:'/usr/bin/node',
OLDPWD:'/home/admin' }

示例

让我们再看一个例子。

// Node.js program to demonstrate the use of process.env

// Importing the process module
const process = require('process');

// Printing object for process.env
var no_env = 0;

// Calling the process.env function
var env = process.env;

// Traversing through the returned data
for (var key in env) {
   // Printing values
   console.log(key + ":\t\t\t" + env[key]);
   no_env++;
}

// Printing total count
console.log("total no of values available = " + no_env);

// Accessing fields one by one
console.log("operating system:" + env['OS']);
console.log("alluserprofile:" + env['ALLUSERSPROFILE']);
console.log("public directory:" + env['PUBLIC']);

输出

admin@root:~/node/test$ node env.js
SHELL:            /bin/bash
SESSION_MANAGER:  local/admin:@/tmp/.ICEunix/2956,unix/admin:/tmp/.ICE-unix/2956
QT_ACCESSIBILITY: 1
COLORTERM:        truecolor
XDG_CONFIG_DIRS:  /etc/xdg/xdg-ubuntu:/etc/xdg
XDG_MENU_PREFIX:  gnomeGNOME_DESKTOP_SESSION_ID:this-is-deprecated
LANGUAGE:         en_IN:en
GNOME_SHELL_SESSION_MODE:ubuntu
SSH_AUTH_SOCK:     /run/user/1001/keyring/ssh
XMODIFIERS:        @im=ibus
DESKTOP_SESSION:   ubuntu
SSH_AGENT_PID:     2912
GTK_MODULES:       gail:atk-bridge
PWD:               /home/admin/test
LOGNAME:           admin
XDG_SESSION_DESKTOP:ubuntu
XDG_SESSION_TYPE:  x11
GPG_AGENT_INFO:    /run/user/1001/gnupg/S.gpg-agent:0:1
XAUTHORITY:        /run/user/1001/gdm/Xauthority
GJS_DEBUG_TOPICS:  JS ERROR;JS LOG
WINDOWPATH:        2
HOME:              /home/admin
USERNAME:          admin
IM_CONFIG_PHASE:   1
LANG:              en_IN
LS_COLORS:
rs=0:di=01;34:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or
=40;31;01:mi=00:su=37;41:sg=30;43:ca=30;41:tw=30;42:ow=34;42:st=37;44:ex=01;32:*.tar=01;
31:*.tgz=01;31:*.arc=01;31:*.arj=01;31:*.taz=01;31:*.lha=01;31:*.lz4=01;31:*.lzh=01;31:*.lzma=0
1;31:*.tlz=01;31:*.txz=01;31:*.tzo=01;31:*.t7z=01;31:*.zip=01;31:*.z=01;31:*.dz=01;31:*.gz=01;3
1:*.lrz=01;31:*.lz=01;31:*.lzo=01;31:*.xz=01;31:*.zst=01;31:*.tzst=01;31:*.bz2=01;31:*.bz=01;31:
*.tbz=01;31:*.tbz2=01;31:*.tz=01;31:*.deb=01;31:*.rpm=01;31:*.jar=01;31:*.war=01;31:*.ear=01;
31:*.sar=01;31:*.rar=01;31:*.alz=01;31:*.ace=01;31:*.zoo=01;31:*.cpio=01;31:*.7z=01;31:*.rz=01
;31:*.cab=01;31:*.wim=01;31:*.swm=01;31:*.dwm=01;31:*.esd=01;31:*.jpg=01;35:*.jpeg=01;35:*
.mjpg=01;35:*.mjpeg=01;35:*.gif=01;35:*.bmp=01;35:*.pbm=01;35:*.pgm=01;35:*.ppm=01;35:*.t
ga=01;35:*.xbm=01;35:*.xpm=01;35:*.tif=01;35:*.tiff=01;35:*.png=01;35:*.svg=01;35:*.svgz=01;3
5:*.mng=01;35:*.pcx=01;35:*.mov=01;35:*.mpg=01;35:*.mpeg=01;35:*.m2v=01;35:*.mkv=01;35:
*.webm=01;35:*.ogm=01;35:*.mp4=01;35:*.m4v=01;35:*.mp4v=01;35:*.vob=01;35:*.qt=01;35:*.n
uv=01;35:*.wmv=01;35:*.asf=01;35:*.rm=01;35:*.rmvb=01;35:*.flc=01;35:*.avi=01;35:*.fli=01;35:*
.flv=01;35:*.gl=01;35:*.dl=01;35:*.xcf=01;35:*.xwd=01;35:*.yuv=01;35:*.cgm=01;35:*.emf=01;35:
*.ogv=01;35:*.ogx=01;35:*.aac=00;36:*.au=00;36:*.flac=00;36:*.m4a=00;36:*.mid=00;36:*.midi=
00;36:*.mka=00;36:*.mp3=00;36:*.mpc=00;36:*.ogg=00;36:*.ra=00;36:*.wav=00;36:*.oga=00;36:
*.opus=00;36:*.spx=00;36:*.xspf=00;36:
XDG_CURRENT_DESKTOP:   ubuntu:GNOME
VTE_VERSION:           6003
GNOME_TERMINAL_SCREEN:
/org/gnome/Terminal/screen/82170ab9_b5b3_424d_b0ce_37a40eb4e264
INVOCATION_ID:         9f9745f4c0c546eaa78b2c84f6d7ae59
MANAGERPID:            2722
GJS_DEBUG_Output:      stderr
LESSCLOSE:            /usr/bin/lesspipe %s %s
XDG_SESSION_CLASS:    user
TERM:                  xterm-256color
LESSOPEN:            - /usr/bin/lesspipe %s
USER:admin
GNOME_TERMINAL_SERVICE::1.111
DISPLAY:               :0
SHLVL:                  1
QT_IM_MODULE:           ibus
XDG_RUNTIME_DIR:        /run/user/1001
JOURNAL_STREAM:         9:66796
XDG_DATA_DIRS:
/usr/share/ubuntu:/usr/local/share/:/usr/share/:/var/lib/snapd/desktop
PATH:
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/
bin
GDMSESSION:            ubuntu
DBUS_SESSION_BUS_ADDRESS:unix:path=/run/user/1001/bus
_:/usr/bin/node
OLDPWD:               /home/admin
total no of values available = 50
operating system:      undefined
alluserprofile:        undefined
public directory:      undefined