How to optimize the first screen loading time in vue

This time I will show you how vue optimizes the first screen loading time. What are the precautions for vue to optimize the first screen loading time. The following is a practical case, let's take a look.

The project requirements of my recent internship did not have many requirements, so I learned about project optimization. The main reason was that the first screen loaded too slowly.

Large file positioning

We can use the webpack visual plug-inWebpack Bundle Analyzer View the project js file size, and then have The purpose is to solve the js file that is too large.

Installation

npm install --save-dev webpack-bundle-analyzer

Set as follows in webpack, and then npm run dev By default, it will be displayed on port 8888.

const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;
module.exports = {
 plugins: [
  new BundleAnalyzerPlugin()
 ]
}

JS files are loaded on demand

Without this setting, all JS files of the entire website will be loaded when the first screen of the project is loaded, so It is a good optimization method to disassemble the JS file and load the JS of a certain page when the page is clicked.

What is used here is the lazy loading of vue components. In router.js, do not use the import method to introduce components, use require.ensure.

import index from '@/components/index'
const index = r => require.ensure( [], () => r (require('@/components/index'),'index'))
//如果写了第二个参数，就打包到该`/JS/index` 的文件中。
//不写第二个参数，就直接打包在`/JS` 目录下。
const index = r => require.ensure( [], () => r (require('@/components/index')))

When using cdn

, replace vue, vuex, vue-router, axios, etc. with domestic bootcdn and directly introduce them to In index.html in the root directory.

Add externals in webpack settings and ignore libraries that do not need to be packaged.

externals: { 
 'vue': 'Vue', 
 'vue-router': 'VueRouter', 
 'vuex': 'Vuex', 
 'axios': 'axios' 
}

Use cdn to import in index.html.

<script src="//cdn.bootcss.com/vue/2.2.5/vue.min.js"></script> 
<script src="//cdn.bootcss.com/vue-router/2.3.0/vue-router.min.js"></script>
<script src="//cdn.bootcss.com/vuex/2.2.1/vuex.min.js"></script> 
<script src="//cdn.bootcss.com/axios/0.15.3/axios.min.js"></script>

Place the JS file at the end of the body

By default, in the built index.html, js is introduced in header.

Use the html-webpack-plugin plug-in and change the value of inject to body. You can put the js introduction at the end of the body.

var HtmlWebpackPlugin = require('html-webpack-plugin');
new HtmlWebpackPlugin({
   inject: 'body',
})

Compress the code and remove the console

Use the UglifyJsPlugin plug-in to compress the code and remove the console.

new webpack.optimize.UglifyJsPlugin({
 compress: {
  warnings: false,
  drop_console: true,
  pure_funcs: ['console.log']
 },
 sourceMap: false
})

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!

Recommended reading:

How does the Angular parent component call the child component

How to submit data in JSON format to the server

How to use WeChat mini program block

The above is the detailed content of How to optimize the first screen loading time in vue. For more information, please follow other related articles on the PHP Chinese website!