How to remove a component dynamically in angular

Question

I went through angular dynamically loading components. But i could not find how to remove the component dynamically.

My requirement is that the chat application loads dynamic component(image/graph/list/table) as per the conversation. But how can i destroy the component if the conversation moves forward.

I am trying to destroy dynamic component with external event.

Please help how to proceed.

EDIT: https://stackblitz.com/angular/emjkxxxdxmk?file=src%2Fapp%2Fad-banner.component.ts

I developed my code according to this example. Instead of time interval, I need to use a API call from a service that is subscribed another component(chat component).

Below API response can load the component.I am looking for how to destroy the already loaded component i use the API call again.

public sendMessage(data): void {
    this.messages.push(this.message);
    this.API.getResponse(data).subscribe(res => {
      this.previousContext = res.context;
      console.log('res', res);
      if (res.result.type == 'table') {
        this.DataService.setTrigger(new AdItem(Table2Component, res));
      }
      this.messages.push(
        new Message(res.text, 'assets/images/bot.png', new Date(), 'chatbot')
      );
    });
    this.message = new Message('', 'assets/images/user.png', this.message.timestamp, 'user');
  }

Solution

Use destroy() method

Destroys the component instance and all of the data structures associated with it.

ref:ComponentRef<any>;
loadComponent() {
    this.currentAdIndex = (this.currentAdIndex + 1) % this.ads.length;
    let adItem = this.ads[this.currentAdIndex];

    let componentFactory = this.componentFactoryResolver.resolveComponentFactory(adItem.component);

    let viewContainerRef = this.adHost.viewContainerRef;
    viewContainerRef.clear();

    let componentRef = viewContainerRef.createComponent(componentFactory);
    this.ref=componentRef;
    (<AdComponent>componentRef.instance).data = adItem.data;

  }

  removeComponent(){
   try{
       this.ref.destroy();
   }
   catch(e){
   }
  }

Example:https://stackblitz.com/edit/destroy?file=src/app/ad-banner.component.ts

Comments

[Sridhar Natuva]

when do i call this method? It works only if the component exits. If the component doesn't exits ref.destroy() is showing error. I tried with the below code.. but it didn't work. if(this.ref!=null){this.ref.destroy();}

[Chellappan வ]

why do you want to destroy if there is no component

[Sridhar Natuva]

If there is no component.. it should not execute that line.. i am unable toput the if condition there. this.ref shows undefined when I console.log(). Please help on the if condition.., it shows undefined..

[Chellappan வ]

instead of if use try catch