边缘浏览器、IE浏览器和旧浏览器中的ViewEncapsulation.ShadowDom支持

Question

我用的是有角度7的材料。我的一些组件使用ShadowDOM ViewEncapsulation，而我在IE、Edge和一些旧版本的Chrome、Firefox中都出现了错误。

以下是错误描述：

对象不支持属性或方法'attachShadow'

此外，我还包括了一些默认的填充，但仍然会发生相同的错误。

/**
 * 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/guide/browser-support
 */

/***************************************************************************************************
 * 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';

/**
 * If the application will be indexed by Google Search, the following is required.
 * Googlebot uses a renderer based on Chrome 41.
 * https://developers.google.com/search/docs/guides/rendering
 **/
import 'core-js/es6/array';

/** 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';

/**
 * 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
 */

Answer 1

我发现我们只需要添加ShadyDOM填充就可以在IE和Edge中支持ViewEncapsulation.ShadowDOM (我没有其他的老浏览器，所以只能在IE和Edge中进行测试)。我从这里中找到了polyfill的链接，并在我的index.html中添加了<script src="https://cdnjs.cloudflare.com/ajax/libs/shadydom/1.1.0/shadydom.min.js"></script>，然后它就工作了。

在我上面的评论中，添加对WebComponentsJs的引用只适用于边缘。但是在IE和Edge中添加shadydom填充都是有效的。