angular - @NgModule.entryComponents 和动态创建的组件

Question

我以两种不同的方式打开模态Stackblitz 示例：

1. 在调用模态服务的组件中调用方法：

   <button (click)="openModal()">Open Modal</button>
   
   export class AppComponent  {
   
     constructor(private modalService: ModalService) { }
   
     openModal() {
       this.modalService.open(HelloComponent);
     }
   
   }
   

   模态服务动态创建组件。

2. 使用然后调用 ModalService 的指令：

   <button [modal]="'HelloComponent'">Open Modal</button>
   
   @Directive({
     selector: '[modal]'
   })
   
   export class ModalDirective {
   
     @Input('modal') identifier: string;
   
     constructor(private modalService: ModalService) { }
   
     @HostListener('click', ['$event'])
     clickEvent(event) {
   
       event.preventDefault();
       event.stopPropagation();
       this.modalService.open(this.identifier);
   
     }
   
   }
   

选项 (1) 工作正常，但选项 (2) 返回错误：

Error: No component factory found for HelloComponent. Did you add it to @NgModule.entryComponents?

我的 AppModule 中有以下内容：

@NgModule({
  imports:      [ BrowserModule, FormsModule ],
  exports:      [ ModalDirective ],
  declarations: [ AppComponent, HelloComponent, ModalDirective ],
  entryComponents: [HelloComponent],
  bootstrap:    [ AppComponent ]
})

所以我不确定为什么这不起作用......

标签： angularangular6angular7

Answer 1

您需要将引用别名为HelloComponent.

更新app.component

export class AppComponent  {

  modalComp = HelloComponent;

  constructor(private modalService: ModalService) { }

  openModal() {
    this.modalService.open(this.modalComp);
  }

}

和模板：

<div style="text-align:center">
  <h1>Modal Example</h1>

  <button (click)="openModal()">Open Modal</button>

  <button [modal]="modalComp">Open Modal</button>

</div>

更新堆栈闪电战：https ://stackblitz.com/edit/mk-angular-modal-service-bzn8z7?file=src%2Fapp%2Fapp.component.html