在 angular 8 中动态添加嵌套组件

Question

I am building an angular 8 application. I have a nested component which I would like to dynamically add on the parent component on clicking of a button on the parent component. Something like this below:

The ADD button should add the component on the parent component. The close button should remove the nested component from the parent component. Also, I would like communication between parent and nested component to happen on clicking some controls on the nested component, like clicking on the Add Student button etc. So far I have been able to create a nested component and add it on the parent component (not dynamic).

Please find the code below:

add-student.component.html

<div class="col-lg-3 col-md-12">
  <div style="float: right;">
    <button type="button" class="close" aria-label="Close">
      <span aria-hidden="true">&times;</span>
    </button>
    <button type="button" class="btn btn-primary">Add Student</button>
  </div>

I know that I can use jquery to dynamically add divs and achieve this. But how can I achieve this using angular ? Is there a better and easier way to accomplish this ?

Thanks

Answer 1

In angular think this way, you have a list of students and you want to add and remove them. components are presentation of data.

Being said you need to do this

in parent component

students: Array<Student> = [];

addStudent() {
 this.students = [...this.students, new Student()];
}

onRemoveStudent(student: Student) {
  const index = this.students.findIndex(student);
  if (index !== -1) {
     this.students.splice(index,1);
  }
}

<div *ngFor="let student of students">
  <app-student [student]="student" (remove)="onRemoveStudent($event)"></app-student>
</div>

in student component

@Input() student: Student;
@Output() remove: EventEmittrer<Student> = new EventEmittrer<Student>();

onRemoveButtonClick() {
  this.remove.emit(this.student);
}

Answer 2

You can achieve this by doing something like

<button (click)="addComponent()"> ADD </button>
<div id="student-components">
   <student-list *ngFor="let component of components" [identifier]="component">

   </student-list>
</div>

components: string[] = [];
addComponent() {
   var id = ""; //generate something like Guid.NewGuid()
   this.components.push(id);
}

and in the add-student.component you can use the id to remove it from the parent component.