Published: 02 Jan 2019 › Updated: 02 Jan 2019
Vue入门基础
Vue是一套用于构建用户界面的渐进式框架。
安装
已经安装nvm
Chaim:vue Chaim$ nvm use v8
Now using node v8.12.0 (npm v6.5.0)
Chaim:vue Chaim$ npm install -g vue-cli
查看帮助
Chaim:vue Chaim$ vue
Usage: vue <command> [options]
Options:
-V, --version output the version number
-h, --help output usage information
Commands:
init generate a new project from a template
list list available official templates
build prototype a new project
create (for v3 warning only)
help [cmd] display help for [cmd]
创建项目
Chaim:vue Chaim$ vue init webpack first-vue
? Project name first-vue
? Project description A Vue.js project
? Author Barnard <yucm@qq.com>
? Vue build standalone
? Install vue-router? Yes
? Use ESLint to lint your code? Yes
? Pick an ESLint preset Airbnb
? Set up unit tests Yes
? Pick a test runner noTest
? Setup e2e tests with Nightwatch? No
? Should we run `npm install` for you after the project has been created? (recommended) no
vue-cli · Generated "first-vue".
# Project initialization finished!
# ========================
To get started:
cd first-vue
npm install (or if using yarn: yarn)
npm run lint -- --fix (or for yarn: yarn run lint --fix)
npm run dev
Documentation can be found at https://vuejs-templates.github.io/webpack
运行
Chaim:first-vue Chaim$ npm install
Chaim:first-vue Chaim$ npm run dev
可以看到编译完成，并在本机8080端口监听的提示：
DONE Compiled successfully in 2540ms 23:10:18
I Your application is running here: http://localhost:8080
用浏览器打开 http://127.0.0.1:8080 即可看到欢迎页面。
项目主要内容
目录结构
先熟悉下vue项目目录结构：
├── README.md 项目介绍
├── index.html 入口页面，页面标题在此修改
├── build 构建脚本目录
│ ├── build.js 生产环境构建脚本
│ ├── check-versions.js 版本检测
│ ├── utils.js 构建相关工具方法
│ ├── vue-loader.conf.js vue-loader根据生产版本还是开发版本加载
│ ├── webpack.base.conf.js webpack基础配置
│ ├── webpack.dev.conf.js webpack开发环境配置
│ └── webpack.prod.conf.js webpack生产环境配置
├── config 项目配置
│ ├── dev.env.js 开发环境变量
│ ├── index.js 项目配置文件
│ ├── prod.env.js 生产环境变量
├── package.json npm包配置文件，里面定义了项目的npm脚本，依赖包等信息
├── src 源码目录
│ ├── main.js 入口js文件
│ ├── App.vue 根组件
│ ├── components 公共组件目录
│ │ └── HelloWorld.vue
│ ├── assets 资源目录，这里的资源会被wabpack构建
│ │ └── logo.png
│ ├── routes 前端路由
│ │ └── index.js
├── static 纯静态资源，不会被wabpack构建
主要文件
再熟悉下主要的文件内容
package.json
package.json主要说明了项目的依赖关系，还有执行类似“npm run dev”命令时的真正调用的指令
"scripts": {
"dev": "webpack-dev-server --inline --progress --config build/webpack.dev.conf.js",
"start": "npm run dev",
"build": "node build/build.js"
},
所以“npm run dev”这个命令实际执行的是：
./node_modules/.bin/webpack-dev-server --inline --progress --config build/webpack.dev.conf.js
build/webpack.dev.conf.js
'use strict'
const utils = require('./utils')
const webpack = require('webpack')
const config = require('../config')
const merge = require('webpack-merge')
const path = require('path')
const baseWebpackConfig = require('./webpack.base.conf')
const CopyWebpackPlugin = require('copy-webpack-plugin')
const HtmlWebpackPlugin = require('html-webpack-plugin')
const FriendlyErrorsPlugin = require('friendly-errors-webpack-plugin')
const portfinder = require('portfinder')
const HOST = process.env.HOST
const PORT = process.env.PORT && Number(process.env.PORT)
const devWebpackConfig = merge(baseWebpackConfig, {
module: {
rules: utils.styleLoaders({ sourceMap: config.dev.cssSourceMap, usePostCSS: true })
},
// cheap-module-eval-source-map is faster for development
devtool: config.dev.devtool,
// these devServer options should be customized in /config/index.js
devServer: {
clientLogLevel: 'warning',
historyApiFallback: {
rewrites: [
{ from: /.*/, to: path.posix.join(config.dev.assetsPublicPath, 'index.html') },
],
},
hot: true,
contentBase: false, // since we use CopyWebpackPlugin.
compress: true,
host: HOST || config.dev.host,
port: PORT || config.dev.port,
open: config.dev.autoOpenBrowser,
overlay: config.dev.errorOverlay
? { warnings: false, errors: true }
: false,
publicPath: config.dev.assetsPublicPath,
proxy: config.dev.proxyTable,
quiet: true, // necessary for FriendlyErrorsPlugin
watchOptions: {
poll: config.dev.poll,
}
},
plugins: [
new webpack.DefinePlugin({
'process.env': require('../config/dev.env')
}),
new webpack.HotModuleReplacementPlugin(),
new webpack.NamedModulesPlugin(), // HMR shows correct file names in console on update.
new webpack.NoEmitOnErrorsPlugin(),
// https://github.com/ampedandwired/html-webpack-plugin
new HtmlWebpackPlugin({
filename: 'index.html',
template: 'index.html',
inject: true
}),
// copy custom static assets
new CopyWebpackPlugin([
{
from: path.resolve(__dirname, '../static'),
to: config.dev.assetsSubDirectory,
ignore: ['.*']
}
])
]
})
module.exports = new Promise((resolve, reject) => {
portfinder.basePort = process.env.PORT || config.dev.port
portfinder.getPort((err, port) => {
if (err) {
reject(err)
} else {
// publish the new Port, necessary for e2e tests
process.env.PORT = port
// add port to devServer config
devWebpackConfig.devServer.port = port
// Add FriendlyErrorsPlugin
devWebpackConfig.plugins.push(new FriendlyErrorsPlugin({
compilationSuccessInfo: {
messages: [`Your application is running here: http://${devWebpackConfig.devServer.host}:${port}`],
},
onErrors: config.dev.notifyOnErrors
? utils.createNotifierCallback()
: undefined
}))
resolve(devWebpackConfig)
}
})
})
这个文件的代码根据不同版本和配置会有不同，主要做以下事情：
- 配置样式文件的处理规则
- 合并配置到base配置
- 定义webpack插件
- devServer的配置项
此文件会引用webpack.base.conf.js
build/webpack.base.conf.js
'use strict'
const path = require('path')
const utils = require('./utils')
const config = require('../config')
const vueLoaderConfig = require('./vue-loader.conf')
function resolve (dir) {
return path.join(__dirname, '..', dir)
}
module.exports = {
context: path.resolve(__dirname, '../'),
entry: {
app: './src/main.js'
},
output: {
path: config.build.assetsRoot,
filename: '[name].js',
publicPath: process.env.NODE_ENV === 'production'
? config.build.assetsPublicPath
: config.dev.assetsPublicPath
},
resolve: {
extensions: ['.js', '.vue', '.json'],
alias: {
'vue$': 'vue/dist/vue.esm.js',
'@': resolve('src'),
}
},
module: {
rules: [
{
test: /\.vue$/,
loader: 'vue-loader',
options: vueLoaderConfig
},
{
test: /\.js$/,
loader: 'babel-loader',
include: [resolve('src'), resolve('test'), resolve('node_modules/webpack-dev-server/client')]
},
{
test: /\.(png|jpe?g|gif|svg)(\?.*)?$/,
loader: 'url-loader',
options: {
limit: 10000,
name: utils.assetsPath('img/[name].[hash:7].[ext]')
}
},
{
test: /\.(mp4|webm|ogg|mp3|wav|flac|aac)(\?.*)?$/,
loader: 'url-loader',
options: {
limit: 10000,
name: utils.assetsPath('media/[name].[hash:7].[ext]')
}
},
{
test: /\.(woff2?|eot|ttf|otf)(\?.*)?$/,
loader: 'url-loader',
options: {
limit: 10000,
name: utils.assetsPath('fonts/[name].[hash:7].[ext]')
}
}
]
},
node: {
// prevent webpack from injecting useless setImmediate polyfill because Vue
// source contains it (although only uses it if it's native).
setImmediate: false,
// prevent webpack from injecting mocks to Node native modules
// that does not make sense for the client
dgram: 'empty',
fs: 'empty',
net: 'empty',
tls: 'empty',
child_process: 'empty'
}
}
主要实现以下功能：
- 配置Webpack编译入口
- 配置Webpack输出路径和命名规则
- 配置模块resolve规则
- 配置不同类型模块的处理规则
如果需要处理其他文件，可以在module.rules里面增加配置。
build/utils.js
'use strict'
const path = require('path')
const config = require('../config')
const ExtractTextPlugin = require('extract-text-webpack-plugin')
const packageConfig = require('../package.json')
exports.assetsPath = function (_path) {
const assetsSubDirectory = process.env.NODE_ENV === 'production'
? config.build.assetsSubDirectory
: config.dev.assetsSubDirectory
return path.posix.join(assetsSubDirectory, _path)
}
exports.cssLoaders = function (options) {
options = options || {}
const cssLoader = {
loader: 'css-loader',
options: {
sourceMap: options.sourceMap
}
}
const postcssLoader = {
loader: 'postcss-loader',
options: {
sourceMap: options.sourceMap
}
}
// generate loader string to be used with extract text plugin
function generateLoaders (loader, loaderOptions) {
const loaders = options.usePostCSS ? [cssLoader, postcssLoader] : [cssLoader]
if (loader) {
loaders.push({
loader: loader + '-loader',
options: Object.assign({}, loaderOptions, {
sourceMap: options.sourceMap
})
})
}
// Extract CSS when that option is specified
// (which is the case during production build)
if (options.extract) {
return ExtractTextPlugin.extract({
use: loaders,
fallback: 'vue-style-loader'
})
} else {
return ['vue-style-loader'].concat(loaders)
}
}
// https://vue-loader.vuejs.org/en/configurations/extract-css.html
return {
css: generateLoaders(),
postcss: generateLoaders(),
less: generateLoaders('less'),
sass: generateLoaders('sass', { indentedSyntax: true }),
scss: generateLoaders('sass'),
stylus: generateLoaders('stylus'),
styl: generateLoaders('stylus')
}
}
// Generate loaders for standalone style files (outside of .vue)
exports.styleLoaders = function (options) {
const output = []
const loaders = exports.cssLoaders(options)
for (const extension in loaders) {
const loader = loaders[extension]
output.push({
test: new RegExp('\\.' + extension + '$'),
use: loader
})
}
return output
}
exports.createNotifierCallback = () => {
const notifier = require('node-notifier')
return (severity, errors) => {
if (severity !== 'error') return
const error = errors[0]
const filename = error.file && error.file.split('!').pop()
notifier.notify({
title: packageConfig.name,
message: severity + ': ' + error.name,
subtitle: filename || '',
icon: path.join(__dirname, 'logo.png')
})
}
}
主要完成以下功能：
- 根据生产还是开发环境，设置资源存储路径
- 生成cssLoaders用于加载.vue文件中的样式
- 生成styleLoaders用于加载不在.vue文件中的样式
- 生成通知回调
build/vue-loader.conf.js
'use strict'
const utils = require('./utils')
const config = require('../config')
const isProduction = process.env.NODE_ENV === 'production'
const sourceMapEnabled = isProduction
? config.build.productionSourceMap
: config.dev.cssSourceMap
module.exports = {
loaders: utils.cssLoaders({
sourceMap: sourceMapEnabled,
extract: isProduction
}),
cssSourceMap: sourceMapEnabled,
cacheBusting: config.dev.cacheBusting,
transformToRequire: {
video: ['src', 'poster'],
source: 'src',
img: 'src',
image: 'xlink:href'
}
}
build/build.js
'use strict'
require('./check-versions')()
process.env.NODE_ENV = 'production'
const ora = require('ora')
const rm = require('rimraf')
const path = require('path')
const chalk = require('chalk')
const webpack = require('webpack')
const config = require('../config')
const webpackConfig = require('./webpack.prod.conf')
const spinner = ora('building for production...')
spinner.start()
rm(path.join(config.build.assetsRoot, config.build.assetsSubDirectory), err => {
if (err) throw err
webpack(webpackConfig, (err, stats) => {
spinner.stop()
if (err) throw err
process.stdout.write(stats.toString({
colors: true,
modules: false,
children: false, // If you are using ts-loader, setting this to true will make TypeScript errors show up during build.
chunks: false,
chunkModules: false
}) + '\n\n')
if (stats.hasErrors()) {
console.log(chalk.red(' Build failed with errors.\n'))
process.exit(1)
}
console.log(chalk.cyan(' Build complete.\n'))
console.log(chalk.yellow(
' Tip: built files are meant to be served over an HTTP server.\n' +
' Opening index.html over file:// won\'t work.\n'
))
})
})
命令行执行“npm run build”会执行“build/build.js”，主要完成以下功能：
- 加载loading动画
- 删除原有文件夹（以前构建的内容）
- 执行Webpack构建
- 输出提示信息
build/webpack.prod.conf.js
'use strict'
const path = require('path')
const utils = require('./utils')
const webpack = require('webpack')
const config = require('../config')
const merge = require('webpack-merge')
const baseWebpackConfig = require('./webpack.base.conf')
const CopyWebpackPlugin = require('copy-webpack-plugin')
const HtmlWebpackPlugin = require('html-webpack-plugin')
const ExtractTextPlugin = require('extract-text-webpack-plugin')
const OptimizeCSSPlugin = require('optimize-css-assets-webpack-plugin')
const UglifyJsPlugin = require('uglifyjs-webpack-plugin')
const env = require('../config/prod.env')
const webpackConfig = merge(baseWebpackConfig, {
module: {
rules: utils.styleLoaders({
sourceMap: config.build.productionSourceMap,
extract: true,
usePostCSS: true
})
},
devtool: config.build.productionSourceMap ? config.build.devtool : false,
output: {
path: config.build.assetsRoot,
filename: utils.assetsPath('js/[name].[chunkhash].js'),
chunkFilename: utils.assetsPath('js/[id].[chunkhash].js')
},
plugins: [
// http://vuejs.github.io/vue-loader/en/workflow/production.html
new webpack.DefinePlugin({
'process.env': env
}),
new UglifyJsPlugin({
uglifyOptions: {
compress: {
warnings: false
}
},
sourceMap: config.build.productionSourceMap,
parallel: true
}),
// extract css into its own file
new ExtractTextPlugin({
filename: utils.assetsPath('css/[name].[contenthash].css'),
// Setting the following option to `false` will not extract CSS from codesplit chunks.
// Their CSS will instead be inserted dynamically with style-loader when the codesplit chunk has been loaded by webpack.
// It's currently set to `true` because we are seeing that sourcemaps are included in the codesplit bundle as well when it's `false`,
// increasing file size: https://github.com/vuejs-templates/webpack/issues/1110
allChunks: true,
}),
// Compress extracted CSS. We are using this plugin so that possible
// duplicated CSS from different components can be deduped.
new OptimizeCSSPlugin({
cssProcessorOptions: config.build.productionSourceMap
? { safe: true, map: { inline: false } }
: { safe: true }
}),
// generate dist index.html with correct asset hash for caching.
// you can customize output by editing /index.html
// see https://github.com/ampedandwired/html-webpack-plugin
new HtmlWebpackPlugin({
filename: config.build.index,
template: 'index.html',
inject: true,
minify: {
removeComments: true,
collapseWhitespace: true,
removeAttributeQuotes: true
// more options:
// https://github.com/kangax/html-minifier#options-quick-reference
},
// necessary to consistently work with multiple chunks via CommonsChunkPlugin
chunksSortMode: 'dependency'
}),
// keep module.id stable when vendor modules does not change
new webpack.HashedModuleIdsPlugin(),
// enable scope hoisting
new webpack.optimize.ModuleConcatenationPlugin(),
// split vendor js into its own file
new webpack.optimize.CommonsChunkPlugin({
name: 'vendor',
minChunks (module) {
// any required modules inside node_modules are extracted to vendor
return (
module.resource &&
/\.js$/.test(module.resource) &&
module.resource.indexOf(
path.join(__dirname, '../node_modules')
) === 0
)
}
}),
// extract webpack runtime and module manifest to its own file in order to
// prevent vendor hash from being updated whenever app bundle is updated
new webpack.optimize.CommonsChunkPlugin({
name: 'manifest',
minChunks: Infinity
}),
// This instance extracts shared chunks from code splitted chunks and bundles them
// in a separate chunk, similar to the vendor chunk
// see: https://webpack.js.org/plugins/commons-chunk-plugin/#extra-async-commons-chunk
new webpack.optimize.CommonsChunkPlugin({
name: 'app',
async: 'vendor-async',
children: true,
minChunks: 3
}),
// copy custom static assets
new CopyWebpackPlugin([
{
from: path.resolve(__dirname, '../static'),
to: config.build.assetsSubDirectory,
ignore: ['.*']
}
])
]
})
if (config.build.productionGzip) {
const CompressionWebpackPlugin = require('compression-webpack-plugin')
webpackConfig.plugins.push(
new CompressionWebpackPlugin({
asset: '[path].gz[query]',
algorithm: 'gzip',
test: new RegExp(
'\\.(' +
config.build.productionGzipExtensions.join('|') +
')$'
),
threshold: 10240,
minRatio: 0.8
})
)
}
if (config.build.bundleAnalyzerReport) {
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin
webpackConfig.plugins.push(new BundleAnalyzerPlugin())
}
module.exports = webpackConfig
主要实现以下功能：
- 合并基础的webpack配置
- 配置样式文件的处理规则，styleLoaders
- 配置webpack的输出
- 配置webpack插件
- gzip模式下的webpack插件配置
- webpack-bundle分析
build/check-version.js
'use strict'
const chalk = require('chalk')
const semver = require('semver')
const packageConfig = require('../package.json')
const shell = require('shelljs')
function exec (cmd) {
return require('child_process').execSync(cmd).toString().trim()
}
const versionRequirements = [
{
name: 'node',
currentVersion: semver.clean(process.version),
versionRequirement: packageConfig.engines.node
}
]
if (shell.which('npm')) {
versionRequirements.push({
name: 'npm',
currentVersion: exec('npm --version'),
versionRequirement: packageConfig.engines.npm
})
}
module.exports = function () {
const warnings = []
for (let i = 0; i < versionRequirements.length; i++) {
const mod = versionRequirements[i]
if (!semver.satisfies(mod.currentVersion, mod.versionRequirement)) {
warnings.push(mod.name + ': ' +
chalk.red(mod.currentVersion) + ' should be ' +
chalk.green(mod.versionRequirement)
)
}
}
if (warnings.length) {
console.log('')
console.log(chalk.yellow('To use this template, you must update following to modules:'))
console.log()
for (let i = 0; i < warnings.length; i++) {
const warning = warnings[i]
console.log(' ' + warning)
}
console.log()
process.exit(1)
}
}
主要完成对node和npm的版本检测。
config/index.js
'use strict'
// Template version: 1.3.1
// see http://vuejs-templates.github.io/webpack for documentation.
const path = require('path')
module.exports = {
dev: {
// Paths
assetsSubDirectory: 'static',
assetsPublicPath: '/',
proxyTable: {},
// Various Dev Server settings
host: 'localhost', // can be overwritten by process.env.HOST
port: 8080, // can be overwritten by process.env.PORT, if port is in use, a free one will be determined
autoOpenBrowser: false,
errorOverlay: true,
notifyOnErrors: true,
poll: false, // https://webpack.js.org/configuration/dev-server/#devserver-watchoptions-
/**
* Source Maps
*/
// https://webpack.js.org/configuration/devtool/#development
devtool: 'cheap-module-eval-source-map',
// If you have problems debugging vue-files in devtools,
// set this to false - it *may* help
// https://vue-loader.vuejs.org/en/options.html#cachebusting
cacheBusting: true,
cssSourceMap: true
},
build: {
// Template for index.html
index: path.resolve(__dirname, '../dist/index.html'),
// Paths
assetsRoot: path.resolve(__dirname, '../dist'),
assetsSubDirectory: 'static',
assetsPublicPath: '/',
/**
* Source Maps
*/
productionSourceMap: true,
// https://webpack.js.org/configuration/devtool/#production
devtool: '#source-map',
// Gzip off by default as many popular static hosts such as
// Surge or Netlify already gzip all static assets for you.
// Before setting to `true`, make sure to:
// npm install --save-dev compression-webpack-plugin
productionGzip: false,
productionGzipExtensions: ['js', 'css'],
// Run the build command with an extra argument to
// View the bundle analyzer report after build finishes:
// `npm run build --report`
// Set to `true` or `false` to always turn it on or off
bundleAnalyzerReport: process.env.npm_config_report
}
}
主要是开发和生产两种环境下的配置，基本上看下文件变量全名和注释就能明白了。
实现原理
双向绑定
使用Object.defineProperty()方法，可以在一个对象上定义一个新属性，或者修改一个对象的现有属性。
大概原理如下：
<input type="text" id="txt" />
<span id="sp"></span>
<script>
var txt = document.getElementById('txt'),
sp = document.getElementById('sp'),
obj = {}
// 给对象obj添加msg属性，并设置setter访问器
Object.defineProperty(obj, 'msg', {
// 设置 obj.msg 当obj.msg反生改变时set方法将会被调用
set: function (newVal) {
// 当obj.msg被赋值时 同时设置给 input/span
txt.value = newVal
sp.innerText = newVal
}
})
// 监听文本框的改变 当文本框输入内容时 改变obj.msg
txt.addEventListener('keyup', function (event) {
obj.msg = event.target.value
})
</script>
通过set方法监控到数据的变化，监听输入控件的数据改变。
Vue不能检测到对象属性的添加和删除，所以属性必须在data对象上存在才能让Vue响应，动态添加的数据默认为非响应式的。
部分内容记录
computed、 method、 watch
computed会缓存数据，只有在依赖变化时才更新。主要用来监控自己定义的变量，该变量不在data里面声明。计算属性是同步的，需要异步时需要用到 vue-async-computed 插件。
watch主要用于监控Vue实例的变化，监控的变量必须在data里面声明，可以监控一个变量，也可以是一个对象。
method每次渲染都会重新计算。
directives
需要对普通DOM元素进行底层操作时，会用到自定义指令。
如官方的聚集输入框例子
参考
https://segmentfault.com/a/1190000006599500
https://segmentfault.com/a/1190000012692321#articleHeader0
https://cn.vuejs.org/v2/guide/reactivity.html
https://www.cnblogs.com/penghuwan/p/6941616.html
https://www.cnblogs.com/wulinzi/p/8109603.html
https://www.w3cplus.com/vue/vue-computed-intro.html
Vue快速入门的三个小实例
https://segmentfault.com/a/1190000012383015
https://blog.csdn.net/hongchh/article/details/55113751/
https://segmentfault.com/a/1190000010801357
仿饿了么
https://blog.csdn.net/qq_39894133/article/details/78826450
vue全家桶
https://blog.csdn.net/zhenghao35791/article/details/67639415
购物车
https://blog.csdn.net/hwhsong/article/details/79885031
路由介绍
https://segmentfault.com/a/1190000011123089?utm_source=tag-newest
Leave Vue入门基础 to:
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