Vue3项目兼容低版本浏览器的全面指南

npm install --save-dev @babel/preset-env @babel/plugin-transform-runtime core-js@3 regenerator-runtime

module.exports = {
  presets: [
    [
      '@babel/preset-env',
      {
        targets: {
          ie: '11',
          chrome: '50'
        },
        useBuiltIns: 'usage',
        corejs: { version: 3, proposals: true },
        debug: true
      }
    ]
  ],
  plugins: [
    ['@babel/plugin-transform-runtime', {
      corejs: 3
    }]
  ]
}

{
  "compilerOptions": {
    "target": "es5",
    "lib": ["es5", "dom", "dom.iterable", "scripthost"],
    "downlevelIteration": true
  }
}

module.exports = {
  transpileDependencies: true,
  configureWebpack: {
    entry: {
      app: ['core-js/stable', 'regenerator-runtime/runtime', './src/main.ts']
    }
  }
}

npm install @vitejs/plugin-legacy --save-dev

import legacy from '@vitejs/plugin-legacy'

​​​​​​​export default defineConfig({
  plugins: [
    legacy({
      targets: ['ie >= 11'],
      additionalLegacyPolyfills: ['regenerator-runtime/runtime']
    })
  ]
})

// 必须放在所有导入之前
import 'core-js/stable'
import 'regenerator-runtime/runtime'

// 可选：针对特定功能的polyfill
import 'core-js/features/promise'
import 'core-js/features/array/includes'
import 'core-js/features/object/assign'
import 'core-js/features/string/includes'

// 解决IE下vue3响应式系统问题
if (typeof window !== 'undefined') {
  if (!window.Promise) {
    window.Promise = Promise
  }
  
  if (!window.Reflect) {
    import('core-js/features/reflect').then(module => {
      window.Reflect = module.default
    })
  }
}

// 避免箭头函数作为方法
const obj = {
  // ❌ 避免
  method: () => { /*...*/ },
  
  // ✅ 推荐
  method: function() { /*...*/ }
}

// 避免使用const/let声明类
// ❌ 避免
const MyClass = class { /*...*/ }

// ✅ 推荐
function MyClass() { /*...*/ }

// 安全使用includes
if (!Array.prototype.includes) {
  import('core-js/features/array/includes')
}

// 安全使用fetch
if (!window.fetch) {
  import('whatwg-fetch').then(({ default: fetch }) => {
    window.fetch = fetch
  })
}

// babel.config.js
module.exports = {
  presets: [
    [
      '@babel/preset-env',
      {
        useBuiltIns: 'entry', // 改为entry模式
        corejs: 3
      }
    ]
  ]
}

// 根据实际需要引入
import 'core-js/features/array'
import 'core-js/features/object'
import 'core-js/features/promise'

// vue.config.js
module.exports = {
  configureWebpack: {
    optimization: {
      splitChunks: {
        cacheGroups: {
          polyfills: {
            test: /[\\/]node_modules[\\/](core-js|regenerator-runtime)[\\/]/,
            name: 'polyfills',
            chunks: 'all'
          }
        }
      }
    }
  }
}

# 安装IE测试工具
npm install --save-dev browser-sync

# 添加测试脚本
"scripts": {
  "test:ie": "browser-sync start --server 'dist' --files 'dist' --browser 'iexplore'"
}

npm install --save-dev @babel/plugin-transform-runtime eslint-plugin-compat

module.exports = {
  plugins: ['compat'],
  rules: {
    'compat/compat': 'error'
  },
  settings: {
    polyfills: ['Promise', 'Array.prototype.includes']
  }
}

// src/utils/compat.ts
import { reactive, watchEffect } from 'vue'

export function ieSafeReactive<T extends object>(obj: T): T {
  if (typeof Proxy !== 'undefined') {
    return reactive(obj)
  }
  
  // IE11降级方案
  const observers = new Set<() => void>()
  const notify = () => observers.forEach(fn => fn())
  
  return Object.keys(obj).reduce((acc, key) => {
    let value = obj[key as keyof T]
    
    Object.defineProperty(acc, key, {
      get() { return value },
      set(newVal) {
        value = newVal
        notify()
      },
      enumerable: true
    })
    
    return acc
  }, {} as T)
}

// vue.config.js
module.exports = {
  transpileDependencies: [
    'vuex', 
    'axios',
    /@vue\/.*/,
    /@babel\/.*/
  ]
}

  if (!window.Promise) {
    document.write('<script src="https://cdn.jsdelivr.net/npm/core-js-bundle@3/minified.js"><\/script>')
  }