vue引入全局sass/less变量、function、mixin

当我们使用vue框架开发的时候，会使用一些全局配置，但是每当我们使用这些全局变量时，每个vue文件或者组件都必须导入该文件@import ‘variables.scss’,那得重复做这样的工作很多很多...次，过程显得非常繁琐。

下面给大家介绍一个解决该难题的办法，好了废话不多说，直接上干货，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

首先招到项目build目录下的util.js文件

'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')
    })
  }
}

我们那sass为例，用sass-resources-loader对其改造： 

  function resolveResouce(name) {
    return path.resolve(__dirname, '../src/styles/' + name)
  }
  function generateSassResourceLoader() {
    var loaders = [
      cssLoader,
      // 'postcss-loader',
      'sass-loader',
      {
        loader: 'sass-resources-loader',
        options: {
          resources: [resolveResouce('mixin.scss'), resolveResouce('variables.scss')] // 需要一个全局路径
        }
      }
    ]
    if (options.extract) {
      return ExtractTextPlugin.extract({
        use: loaders,
        fallback: 'vue-style-loader'
      })
    } else {
      return ['vue-style-loader'].concat(loaders)
    }
  }

然后对return进行修改 

  return {
    css: generateLoaders(),
    postcss: generateLoaders(),
    less: generateLoaders('less'),
    // sass: generateLoaders('sass', { indentedSyntax: true }),
    // scss: generateLoaders('sass')
    sass: generateSassResourceLoader(),
    scss: generateSassResourceLoader(), // 全局变量及mixin配置
    stylus: generateLoaders('stylus'),
    styl: generateLoaders('stylus')
  }

现在大功告成，便可以直接在任何vue页面中使用mixin或变量了

<style lang="scss" scoped>
.form-query {
  @include display-flex;
}
</style>