包含babel polyfill,但forEach仍然无法在NodeLists上的IE11中工作

Question

我得的WebPack与巴贝尔工作,包括@通天塔/填充工具,还试图使用时IE11仍是投掷SCRIPT438错误.forEach上NodeList.

这是我的 package.json

{
  ...
  "scripts": {
    "build:js": "webpack --config ./_build/webpack.config.js"
  },
  ...
  "browserslist": [
    "IE 11",
    "last 3 versions",
    "not IE < 11"
  ],
  "babel": {
    "presets": [
      [
        "@babel/preset-env",
        {
          "useBuiltIns": "usage"
        }
      ]
    ]
  },
  "devDependencies": {
    "@babel/core": "^7.1.6",
    "@babel/preset-env": "^7.1.6",
    "babel-loader": "^8.0.4",
    "webpack": "^4.25.1",
    "webpack-cli": "^3.1.2"
  },
  "dependencies": {
    "@babel/polyfill": "^7.0.0"
  }
}

我的webpack.config.js:

const path = require('path');
const webpack = require('webpack');

module.exports = (env, argv) => {

  const javascript = {
    test: /\.js$/,
    use: {
      loader: 'babel-loader'
    }
  };

  // config object
  const config = {
    entry: {
      main: './_src/js/main.js',
    },
    devtool: 'source-map',
    output: {
      path: path.resolve(__dirname, '../js'),
      filename: '[name].js',
    },
    module: {
      rules: [javascript]
    }
  }

  return config;
}

最后/_src/main.js,我正在通过webpack和babel运行:

const testList = document.querySelectorAll('.test-list li');

testList.forEach(item => {
  console.log(item.innerHTML);
})

https://babeljs.io/docs/en/babel-polyfill上的文档说您不需要import或require polyfill通过Webpack加载它时useBuiltIns: "usage".但即使我删除该选项并手动导入整个polyfill顶部main.js(使我的捆绑巨大),它仍然在IE11中出错.

那么......我做错了什么？

Answer 1

babel-polyfill不会填充缺少的Web API /原型方法 core-js.

另请注意,您的问题标题具有误导性,因为@babel/polyfill它不是ES6功能.core-js可迭代收集目前只是候选推荐(截至2018年8月).

只需在Javascript的顶层包含您自己的polyfill:

if (window.NodeList && !NodeList.prototype.forEach) {
    NodeList.prototype.forEach = Array.prototype.forEach;
}

一旦core-js 3稳定,这可能会改变:https://github.com/zloirock/core-js/issues/329

如果您开始采用ES6中使用的常用模式,您也可以不使用任何polyfill:

const testList = [...document.querySelectorAll('.test-list li')];

要么

const testList = Array.from(document.querySelectorAll('.test-list li'));

您拥有的另一个选择是使用forEach:

const lis = document.querySelectorAll('.test-list li');
for (const li of lis) {
  // li.addEventListener(...) or whatever
}

最后,您还可以采用常见的ES5模式:

var testList = document.querySelectorAll('.test-list li');
Array.prototype.forEach.call(testList, function(li) { /*whatever*/ });