小编Ale*_* JM的帖子

在给定条件的情况下,我想异步地将一个组件附加到路由.

以下示例(可以是异步的)根据用户角色加载一个或另一个组件:

import { UserDashboardComponent }  from './user-dashboard.component'
import { AdminDashboardComponent } from './admin-dashboard.component'

const role = 'admin' // Just for the example
const comp = role === 'admin' ? AdminDashboardComponent : UserDashboardComponent

const routes: Routes = [
  { path: '', component: comp },
]

但是,假设我们想要从API检索角色,从而异步.有什么方法可以实现这一目标？

高阶组件(HOC)是React社区中常见的模式.如果您不知道什么是HOC,请参阅此文章

他们在Angular 2中有意义吗？如何制作HOC？任何例子？

我正在使用装饰器将变量添加到指令的隔离范围.但不知何故,它不起作用,我几乎尝试了一切.

精确指令是angular-ui之一:

.directive('accordionGroup', function() {
  return {
    require:'^accordion',         // We need this directive to be inside an accordion
    restrict:'EA',
    transclude:true,              // It transcludes the contents of the directive into the template
    replace: true,                // The element containing the directive will be replaced with the template
    templateUrl:'template/accordion/accordion-group.html',
    scope: {
      heading: '@',               // Interpolate the heading attribute onto this scope
      isOpen: '=?',
      isDisabled: '=?'
    },
    ...
})

$ decorator代码,我用它来更改模板并添加一个新变量:

mainModule.config(['$provide', function ($provide){

    $provide.decorator('accordionGroupDirective', function($delegate) { 
          var directive = $delegate[0];
          directive.templateUrl = "views/parts/accordion-unit.html"; …