typescript - 类型 'FormArray' 不可分配给类型 'any[]' 。类型 'includes' 中缺少属性 'FormArray'。在angular6 typescript 中

Question

如何解决下面提到的错误:

Type 'FormArray' is not assignable to type 'any[]'. Property 'includes' is missing in type 'FormArray'. in line " this.items = this.AddUserstep2Form.get('items') as FormArray;"

我有下面提到的 ts 文件。请帮助我。

import { FormBuilder, FormGroup, Validators ,FormArray} from '@angular/forms';

 AddUserstep2Form: FormGroup;   items: any[] = [];

 ngOnInit() {
    this.AddUserstep2Form = this.fb.group({

      stateCode: ['',Validators.required],
      cityId:['',Validators.required],
      items: this.fb.array([ this.createItem() ])

    })

createItem(): FormGroup {
    return this.fb.group({
      stateCode: '',
      cityId: ''
    });
  }
  addItem(): void {
    this.items = this.AddUserstep2Form.get('items') as FormArray;
    this.items.push(this.createItem());
  }

Answer 1

如果您需要组件的 items 属性，只需将其当前类型替换为 FormArray:

items: FormArray = new FormArray([]);

如果除了 addItem 方法之外没有在任何地方使用它，那么您可以将它从组件中完全删除并将 addItem 更改为:

addItem(): void {
    const items = this.AddUserstep2Form.get('items') as FormArray;
    items.push(this.createItem());
}