当目标为 es6 时，Angular 应用程序未在 IE 11 中加载

Question

我正在创建一个新应用程序，我的目标浏览器是 IE11。当我将目标用作 es6 时，我的应用无法加载并显示如下所示的错误。

但是当我将目标更改为 es5 时，一切似乎都正常。我的疑问是，添加 polyfill 是为了确保旧版浏览器支持较新的 JavaScript 函数。我已经启用了所有针对 es6 的 polyfill，如下所示

/**
 * This file includes polyfills needed by Angular and is loaded before the app.
 * You can add your own extra polyfills to this file.
 *
 * This file is divided into 2 sections:
 *   1. Browser polyfills. These are applied before loading ZoneJS and are sorted by browsers.
 *   2. Application imports. Files imported after ZoneJS that should be loaded before your main
 *      file.
 *
 * The current setup is for so-called "evergreen" browsers; the last versions of browsers that
 * automatically update themselves. This includes Safari >= 10, Chrome >= 55 (including Opera),
 * Edge >= 13 on the desktop, and iOS 10 and Chrome on mobile.
 *
 * Learn more in https://angular.io/docs/ts/latest/guide/browser-support.html
 */

/***************************************************************************************************
 * BROWSER POLYFILLS
 */

/** IE9, IE10 and IE11 requires all of the following polyfills. **/
import 'core-js/es6/symbol';
import 'core-js/es6/object';
import 'core-js/es6/function';
import 'core-js/es6/parse-int';
import 'core-js/es6/parse-float';
import 'core-js/es6/number';
import 'core-js/es6/math';
import 'core-js/es6/string';
import 'core-js/es6/date';
import 'core-js/es6/array';
import 'core-js/es6/regexp';
import 'core-js/es6/map';
import 'core-js/es6/weak-map';
import 'core-js/es6/set';

/** IE10 and IE11 requires the following for NgClass support on SVG elements */
import 'classlist.js';  // Run `npm install --save classlist.js`.

/** IE10 and IE11 requires the following for the Reflect API. */
import 'core-js/es6/reflect';


/** Evergreen browsers require these. **/
// Used for reflect-metadata in JIT. If you use AOT (and only Angular decorators), you can remove.
import 'core-js/es7/reflect';


/**
 * Web Animations `@angular/platform-browser/animations`
 * Only required if AnimationBuilder is used within the application and using IE/Edge or Safari.
 * Standard animation support in Angular DOES NOT require any polyfills (as of Angular 6.0).
 **/
// import 'web-animations-js';  // Run `npm install --save web-animations-js`.

/**
 * By default, zone.js will patch all possible macroTask and DomEvents
 * user can disable parts of macroTask/DomEvents patch by setting following flags
 */

 // (window as any).__Zone_disable_requestAnimationFrame = true; // disable patch requestAnimationFrame
 // (window as any).__Zone_disable_on_property = true; // disable patch onProperty such as onclick
 // (window as any).__zone_symbol__BLACK_LISTED_EVENTS = ['scroll', 'mousemove']; // disable patch specified eventNames

 /*
 * in IE/Edge developer tools, the addEventListener will also be wrapped by zone.js
 * with the following flag, it will bypass `zone.js` patch for IE/Edge
 */
// (window as any).__Zone_enable_cross_context_check = true;

/***************************************************************************************************
 * Zone JS is required by default for Angular itself.
 */
import 'zone.js/dist/zone';  // Included with Angular CLI.



/***************************************************************************************************
 * APPLICATION IMPORTS
 */

我的问题是，即使所有针对 es6 的 polyfill 都已导入，为什么我的应用程序不来？我在这里错过了什么吗？请帮忙。

对建议重复的回应

我相信这不是this question 的重复。我有解决方案（将 ES6 更改为 ES5）。但是该问题的答案并没有说明为什么即使添加了 polyfill 也不支持 ES6。我相信这个问题与预期的答案完全不同。

Answer 1

正如 Angular 文档所述：Differential loading is currently only supported when using es2015 as a compilation target. When used with targets higher than es2015, a warning is emitted during build time. https://v8.angular.io/guide/deployment#differential-loading

这仅仅意味着在tsconfig中你必须使用"target": "es2015",

您还必须确保正确配置 browserslist（或 package.json）文件。可能你想添加一个 zone-flags.ts。

最后，如果您使用 Object.values 之类的东西，您还必须将 import 'core-js/es7/object'; 放入您的 polyfills 文件中，当然如果您使用其他东西的话。

Answer 2

您的应用无法运行，因为 IE11 不支持大多数 ES6 功能。您必须在 ES5 中定位您的应用程序。

您可以在此处查看 ES6 对 IE11 的支持：ECMA compatibilty