如何在Angular中设置arrayform？

import { FormsModule, ReactiveFormsModule } from '@angular/forms';

@NgModule({
  imports: [
    FormsModule,
    ReactiveFormsModule
  ],
  ...
})
export class YourModule { }

<form [formGroup]="myForm" (ngSubmit)="onSubmit()">
  <div formArrayName="items">
    <div *ngFor="let item of items.controls; let i=index">
      <div [formGroupName]="i">
        <input formControlName="name" placeholder="Item Name">
        <input formControlName="quantity" placeholder="Item Quantity">
        <button (click)="removeItem(i)">Remove Item</button>
      </div>
    </div>
  </div>
  <button (click)="addItem()">Add Item</button>
  <button type="submit">Submit</button>
</form>

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

@Component({
  ...
})
export class YourComponent implements OnInit {
  myForm: FormGroup;

  constructor(private fb: FormBuilder) { }

  ngOnInit() {
    this.myForm = this.fb.group({
      items: this.fb.array([])
    });
  }

  get items() {
    return this.myForm.get('items') as FormArray;
  }

  addItem() {
    const newItem = this.fb.group({
      name: '',
      quantity: ''
    });

    this.items.push(newItem);
  }

  removeItem(index: number) {
    this.items.removeAt(index);
  }

  onSubmit() {
    console.log(this.myForm.value);
  }
}