vue-cli项目优化方法- 缩短首屏加载时间

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

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

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')))

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

<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>

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

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