在angular中使用FormArray

import { Component } from '@angular/core';
import { FormGroup, FormControl, FormArray } from '@angular/forms';

@Component({
  selector: 'app-my-form',
  templateUrl: './my-form.component.html',
  styleUrls: ['./my-form.component.css']
})
export class MyFormComponent {
  myForm: FormGroup;

  constructor() {
    this.myForm = new FormGroup({
      myArray: new FormArray([])
    });
  }
}

<form [formGroup]="myForm">
  <div formArrayName="myArray">
    <div *ngFor="let control of myForm.get('myArray').controls; let i = index">
      <input [formControlName]="i">
    </div>
  </div>
</form>

addComponent() {
  const control = new FormControl();
  (this.myForm.get('myArray') as FormArray).push(control);
}

removeComponent(index: number) {
  (this.myForm.get('myArray') as FormArray).removeAt(index);
}

updateComponent(index: number, value: any) {
  (this.myForm.get('myArray') as FormArray).at(index).patchValue(value);
}