让我们考虑下场景:当使用rem/vw开发移动端的时候，你定义了一个px转rem的函数,或者是网站配色的全局变量等，然后到工程里为每个vue文件或者组件@import ‘publicfilename.scss',那得重复做这样的工作很多很多...次，万一这些公用文件目录路径变怎么办呢，哭都来不及，想想都觉得恐怖呀！
接下来拯救我们的神器就要登场了---sass-resources-loader,它可以省去重复性的引入，还支持less,postcss等，具体用法如下：
npm install -d sass-resource-loader
首先我们找到项目里build目录，在该目录下找到util.js
更新前util.js代码如下:
'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 } } // 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') }) } } /** * 增加 hljs 的 classname */ exports.wrapCustomClass = function (render) { return function (...args) { return render(...args) .replace('<codehljs ') .replace('<code>', '<code>') } } /** * Format HTML string */ exports.convertHtml = function (str) { return str.replace(/(&#x)(\w{4});/gi, $0 => String.fromCharCode(parseInt(encodeURIComponent($0).replace(/(%26%23x)(\w{4})(%3B)/g, '$2'), 16))) }
看util.js文件，我们首先找到我需要修改目标在哪：
// 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') }
我们那sass为例，用sass-resources-loader对其改造：
/** * sass Less 源文件 * @param name classFile * @returns {string} */ function resolveResouce(name) { return path.resolve(__dirname, '../static/' + name); } //导入全局sass mixin function等 function generateSassResourceLoader(){ var loaders = [ cssLoader, //'postcss-loader', 'sass-loader', { loader:'sass-resources-loader', options: { //需要一个全局路径 resources: [resolveResouce('index.scss')] } } ] if(options.extract){ return ExtractTextPlugin.extract({ use:loaders, fallback: 'vue-style-loader' }) }else{ return ['vue-style-loader'].concat(loaders) } }
工具写好好了，接下来直接把上门return对象做些调整，代码如下
// https://vue-loader.vuejs.org/en/configurations/extract-css.html return { css: generateLoaders(), postcss: generateLoaders(), less: generateLoaders('less'), sass:generateSassResourceLoader(), scss:generateSassResourceLoader(), stylus: generateLoaders('stylus'), styl: generateLoaders('stylus') }
从代码中可以看出，我们把sass和scss的loader换成我们自己根据sass-resources-loader写的方法了，这样就实现了我们的目标。