一步一步在 Windows 安装配置 Node.js 和 npm

零、Node.js 与 npm 的关系

Node.js 是一个基于 Chrome V8 引擎的 JavaScript 运行环境。我们如果想愉快的使用 JavaScript 做一些东西，node.js 是必须安装的工具。

在实际工作中，我们会用到很多大佬写的 JavaScript 包或模块。如果每次都根据包命搜索官网或GitHub，下载代码，解压，再使用，而且要解决包之间的依赖关系，随着项目需要的包越来越多，那么这将会是一项非常繁琐工作。为了方便地搜索并安装这些包，我们急需一个包管理器，NPM随后被开发出来。它帮我们安装，删除，更新，最主要是解决这些包的依赖关系。总之，npm 相当于开发者的管家，让我们避免解决这些琐事，专注于 JavaScript 的应用开发。

一、下载及安装

1.下载

https://nodejs.org/en/download/current/

2.安装

next
next
这里选择安装目录

选安装目录时候，需要注意没必要安装在C盘，后续安装包会占用资源。建议在其他盘创建目录，然后以node版本号命名的方式安装。比如我的为E:\node\node-12.16.2
next
next
install
安装完成
安装后，点击回车关闭窗口

3.检测是否安装成功

使用win+R打开cmd：
输入node --version
如果显示如下内容，node 安装成功
输入npm --version
如果显示如下内容，npm 安装成功

二、配置

配置 npm 的模块全局存放路径和缓存路径

打开cmd，输入命令

npm config set prefix "E:\nodejs\node-12.16.2"
npm config set cache"E:\nodejs\node-12.16.2"

现在尝试安装一个包
npm install express -g
这里的-g指的是全局安装。会安装到我们设置的目录下比如 E:\nodejs\node-12.16.2\node_modules

如果没有这个参数的命令 npm install express 叫做本地安装。将安装包放在 ./node_modules 下（运行 npm 命令时所在的目录），如果没有 node_modules 目录，会在当前执行 npm 命令的目录下生成 node_modules 目录。
我们检查包的安装位置E:\nodejs\node-12.16.2\node_modules\express

cnpm 的安装

在实际使用时，安装部分包会发现npm 奇慢无比，这是因为npm的包仓库在国外。为了解决这个问题，需要使用淘宝提供的cnpm作为管理工具，下面我们来安装
打开cmd，输入npm install -g cnpm --registry=https://registry.npm.taobao.org
安装完成，我们测试是否安装成功cnpm -v
如果出现如下，则安装成功

三、NPM 使用

1.安装模块

npm install express      # 本地安装     
npm install express -g   # 全局安装

2.卸载

npm uninstall express

3.更新

npm update express

4.搜索

npm search express

5.查看安装信息

npm list -g

6.查看模块版本号

npm list grunt

7.Package.json

package.json 位于项目的node_modules目录下，用于管理项目用到的包。
同时，package.json 位于包的目录下，用于定义包的属性。看下刚刚安装的 express 包的 package.json 文件，位于 E:\nodejs\node-12.16.2\node_modules\express/package.json 内容及每个字段的介绍：

name: 包名
version: 包的版本号
description: 包的描述
homepage: 包的官网 url
author: 包的作者姓名
contributors: 包的其他贡献者姓名
dependencies: 依赖包列表。如果依赖包没有安装，npm 会自动将依赖包安装在 node_module 目录下
repository: 包代码存放的地方的类型，可以是 git 或 svn，git 可在 Github 上
main: main 字段指定了程序的主入口文件，require(‘moduleName’) 就会加载这个文件。这个字段的默认值是模块根目录下面的 index.js
keywords: 关键字

{
  "_from": "express",
  "_id": "express@4.17.1",
  "_inBundle": false,
  "_integrity": "sha512-mHJ9O79RqluphRrcw2X/GTh3k9tVv8YcoyY4Kkh4WDMUYKRZUq0h1o0w2rrrxBqM7VoeUVqgb27xlEMXTnYt4g==",
  "_location": "/express",
  "_phantomChildren": {},
  "_requested": {
    "type": "tag",
    "registry": true,
    "raw": "express",
    "name": "express",
    "escapedName": "express",
    "rawSpec": "",
    "saveSpec": null,
    "fetchSpec": "latest"
  },
  "_requiredBy": [
    "#USER"
  ],
  "_resolved": "https://registry.npmjs.org/express/-/express-4.17.1.tgz",
  "_shasum": "4491fc38605cf51f8629d39c2b5d026f98a4c134",
  "_spec": "express",
  "_where": "C:\\Users\\Administrator",
  "author": {
    "name": "TJ Holowaychuk",
    "email": "tj@vision-media.ca"
  },
  "bugs": {
    "url": "https://github.com/expressjs/express/issues"
  },
  "bundleDependencies": false,
  "contributors": [
    {
      "name": "Aaron Heckmann",
      "email": "aaron.heckmann+github@gmail.com"
    },
    {
      "name": "Ciaran Jessup",
      "email": "ciaranj@gmail.com"
    },
    {
      "name": "Douglas Christopher Wilson",
      "email": "doug@somethingdoug.com"
    },
    {
      "name": "Guillermo Rauch",
      "email": "rauchg@gmail.com"
    },
    {
      "name": "Jonathan Ong",
      "email": "me@jongleberry.com"
    },
    {
      "name": "Roman Shtylman",
      "email": "shtylman+expressjs@gmail.com"
    },
    {
      "name": "Young Jae Sim",
      "email": "hanul@hanul.me"
    }
  ],
  "dependencies": {
    "accepts": "~1.3.7",
    "array-flatten": "1.1.1",
    "body-parser": "1.19.0",
    "content-disposition": "0.5.3",
    "content-type": "~1.0.4",
    "cookie": "0.4.0",
    "cookie-signature": "1.0.6",
    "debug": "2.6.9",
    "depd": "~1.1.2",
    "encodeurl": "~1.0.2",
    "escape-html": "~1.0.3",
    "etag": "~1.8.1",
    "finalhandler": "~1.1.2",
    "fresh": "0.5.2",
    "merge-descriptors": "1.0.1",
    "methods": "~1.1.2",
    "on-finished": "~2.3.0",
    "parseurl": "~1.3.3",
    "path-to-regexp": "0.1.7",
    "proxy-addr": "~2.0.5",
    "qs": "6.7.0",
    "range-parser": "~1.2.1",
    "safe-buffer": "5.1.2",
    "send": "0.17.1",
    "serve-static": "1.14.1",
    "setprototypeof": "1.1.1",
    "statuses": "~1.5.0",
    "type-is": "~1.6.18",
    "utils-merge": "1.0.1",
    "vary": "~1.1.2"
  },
  "deprecated": false,
  "description": "Fast, unopinionated, minimalist web framework",
  "devDependencies": {
    "after": "0.8.2",
    "connect-redis": "3.4.1",
    "cookie-parser": "~1.4.4",
    "cookie-session": "1.3.3",
    "ejs": "2.6.1",
    "eslint": "2.13.1",
    "express-session": "1.16.1",
    "hbs": "4.0.4",
    "istanbul": "0.4.5",
    "marked": "0.6.2",
    "method-override": "3.0.0",
    "mocha": "5.2.0",
    "morgan": "1.9.1",
    "multiparty": "4.2.1",
    "pbkdf2-password": "1.2.1",
    "should": "13.2.3",
    "supertest": "3.3.0",
    "vhost": "~3.0.2"
  },
  "engines": {
    "node": ">= 0.10.0"
  },
  "files": [
    "LICENSE",
    "History.md",
    "Readme.md",
    "index.js",
    "lib/"
  ],
  "homepage": "http://expressjs.com/",
  "keywords": [
    "express",
    "framework",
    "sinatra",
    "web",
    "rest",
    "restful",
    "router",
    "app",
    "api"
  ],
  "license": "MIT",
  "name": "express",
  "repository": {
    "type": "git",
    "url": "git+https://github.com/expressjs/express.git"
  },
  "scripts": {
    "lint": "eslint .",
    "test": "mocha --require test/support/env --reporter spec --bail --check-leaks test/ test/acceptance/",
    "test-ci": "istanbul cover node_modules/mocha/bin/_mocha --report lcovonly -- --require test/support/env --reporter spec --check-leaks test/ test/acceptance/",
    "test-cov": "istanbul cover node_modules/mocha/bin/_mocha -- --require test/support/env --reporter dot --check-leaks test/ test/acceptance/",
    "test-tap": "mocha --require test/support/env --reporter tap --check-leaks test/ test/acceptance/"
  },
  "version": "4.17.1"
{
  "_from": "express",
  "_id": "express@4.17.1",
  "_inBundle": false,
  "_integrity": "sha512-mHJ9O79RqluphRrcw2X/GTh3k9tVv8YcoyY4Kkh4WDMUYKRZUq0h1o0w2rrrxBqM7VoeUVqgb27xlEMXTnYt4g==",
  "_location": "/express",
  "_phantomChildren": {},
  "_requested": {
    "type": "tag",
    "registry": true,
    "raw": "express",
    "name": "express",
    "escapedName": "express",
    "rawSpec": "",
    "saveSpec": null,
    "fetchSpec": "latest"
  },
  "_requiredBy": [
    "#USER"
  ],
  "_resolved": "https://registry.npmjs.org/express/-/express-4.17.1.tgz",
  "_shasum": "4491fc38605cf51f8629d39c2b5d026f98a4c134",
  "_spec": "express",
  "_where": "C:\\Users\\Administrator",
  "author": {
    "name": "TJ Holowaychuk",
    "email": "tj@vision-media.ca"
  },
  "bugs": {
    "url": "https://github.com/expressjs/express/issues"
  },
  "bundleDependencies": false,
  "contributors": [
    {
      "name": "Aaron Heckmann",
      "email": "aaron.heckmann+github@gmail.com"
    },
    {
      "name": "Ciaran Jessup",
      "email": "ciaranj@gmail.com"
    },
    {
      "name": "Douglas Christopher Wilson",
      "email": "doug@somethingdoug.com"
    },
    {
      "name": "Guillermo Rauch",
      "email": "rauchg@gmail.com"
    },
    {
      "name": "Jonathan Ong",
      "email": "me@jongleberry.com"
    },
    {
      "name": "Roman Shtylman",
      "email": "shtylman+expressjs@gmail.com"
    },
    {
      "name": "Young Jae Sim",
      "email": "hanul@hanul.me"
    }
  ],
  "dependencies": {
    "accepts": "~1.3.7",
    "array-flatten": "1.1.1",
    "body-parser": "1.19.0",
    "content-disposition": "0.5.3",
    "content-type": "~1.0.4",
    "cookie": "0.4.0",
    "cookie-signature": "1.0.6",
    "debug": "2.6.9",
    "depd": "~1.1.2",
    "encodeurl": "~1.0.2",
    "escape-html": "~1.0.3",
    "etag": "~1.8.1",
    "finalhandler": "~1.1.2",
    "fresh": "0.5.2",
    "merge-descriptors": "1.0.1",
    "methods": "~1.1.2",
    "on-finished": "~2.3.0",
    "parseurl": "~1.3.3",
    "path-to-regexp": "0.1.7",
    "proxy-addr": "~2.0.5",
    "qs": "6.7.0",
    "range-parser": "~1.2.1",
    "safe-buffer": "5.1.2",
    "send": "0.17.1",
    "serve-static": "1.14.1",
    "setprototypeof": "1.1.1",
    "statuses": "~1.5.0",
    "type-is": "~1.6.18",
    "utils-merge": "1.0.1",
    "vary": "~1.1.2"
  },
  "deprecated": false,
  "description": "Fast, unopinionated, minimalist web framework",
  "devDependencies": {
    "after": "0.8.2",
    "connect-redis": "3.4.1",
    "cookie-parser": "~1.4.4",
    "cookie-session": "1.3.3",
    "ejs": "2.6.1",
    "eslint": "2.13.1",
    "express-session": "1.16.1",
    "hbs": "4.0.4",
    "istanbul": "0.4.5",
    "marked": "0.6.2",
    "method-override": "3.0.0",
    "mocha": "5.2.0",
    "morgan": "1.9.1",
    "multiparty": "4.2.1",
    "pbkdf2-password": "1.2.1",
    "should": "13.2.3",
    "supertest": "3.3.0",
    "vhost": "~3.0.2"
  },
  "engines": {
    "node": ">= 0.10.0"
  },
  "files": [
    "LICENSE",
    "History.md",
    "Readme.md",
    "index.js",
    "lib/"
  ],
  "homepage": "http://expressjs.com/",
  "keywords": [
    "express",
    "framework",
    "sinatra",
    "web",
    "rest",
    "restful",
    "router",
    "app",
    "api"
  ],
  "license": "MIT",
  "name": "express",
  "repository": {
    "type": "git",
    "url": "git+https://github.com/expressjs/express.git"
  },
  "scripts": {
    "lint": "eslint .",
    "test": "mocha --require test/support/env --reporter spec --bail --check-leaks test/ test/acceptance/",
    "test-ci": "istanbul cover node_modules/mocha/bin/_mocha --report lcovonly -- --require test/support/env --reporter spec --check-leaks test/ test/acceptance/",
    "test-cov": "istanbul cover node_modules/mocha/bin/_mocha -- --require test/support/env --reporter dot --check-leaks test/ test/acceptance/",
    "test-tap": "mocha --require test/support/env --reporter tap --check-leaks test/ test/acceptance/"
  },
  "version": "4.17.1"
}