npm run preview -- --report
将几个比较大的多在打包时排除，这样可以缩小整体打包的大小，保证js的加载速度，排除的包采用cdn的方式用外链去引入，cdn本名为分发服务器，意为更近的访问区间更快的访问速度将所需要的文件返回给客户端
webpack排除打包-代码位置(vue.config.js)
configureWebpack: {
// provide the app's title in webpack's name field, so that
// it can be accessed in index.html to inject the correct title.
name: name,
resolve: {
alias: {
'@': resolve('src')
}
},
// 配置需要排出的包
externals: {
'vue': 'Vue',//前面是包名，后面是替代的变量名称
'element-ui': 'ELEMENT',
}
},在html中采用外链引入排除的文件-代码位置(public/index.html)
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"> <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no"> <link rel="icon" href="<%= BASE_URL %>favicon.ico"> <title><%= webpackConfig.name %></title> <link href="https://cdn.bootcdn.net/ajax/libs/element-ui/2.15.13/theme-chalk/index.min.css" rel="stylesheet"> </head> <body> <noscript> <strong>We're sorry but <%= webpackConfig.name %> doesn't work properly without JavaScript enabled. Please enable it to continue.</strong> </noscript> <div id="app"></div> <!-- built files will be auto injected --> <script src="https://lf9-cdn-tos.bytecdntp.com/cdn/expire-1-M/vue/2.6.14/vue.min.js"></script> <script src="https://cdn.bootcdn.net/ajax/libs/element-ui/2.15.13/index.min.js"></script> </body> </html>