角4中Formarray内部的formArray

Question

我试图在formarray内部实现formarray，但它不起作用，在下面也尝试过，但不起作用。

How to get FormArrayName when the FormArray is nested in another FormArray?

有谁能帮我一下，我在哪里做错了下面的代码

<div [formGroup]="MainFormGroup" class="custom-auto-complete">
  <mat-radio-group matInput formControlName="Applies">
    <mat-radio-button *ngFor="let applie of applies" [value]="applie.id">{{applie.value}}</mat-radio-button>
  </mat-radio-group>           
  <div formArrayName="FormArrayOne">
    <div *ngFor="let mains of MainFormGroup.get('FormArrayOne')['controls']; let i=index">
      <div [formGroupName]="i">
        <mat-icon *ngIf="MainFormGroup.get('FormArrayOne').length > 1" (click)="removeMarket(i)">remove_circle</mat-icon>
        <mat-icon (click)="addOne()"> add_circle</mat-icon>
        <mat-form-field>
          <input matInput formControlName="OneField" value="">
        </mat-form-field>
        <div formArrayName="FormArrayTwo">
          <div *ngFor="let Market of MainFormGroup.get('FormArrayTwo')['controls']; let j=index" >
            <div [formGroupName]="j">            
              <mat-form-field class="formfieldsControl">
                <input matInput formControlName="Destination">
              </mat-form-field>
            </div>
          </div>
        </div>         
      </div>
    </div>
  </div>    
</div>

TS

public ngOnInit() {
  this.MaintFormGroup = this._fb.group({
    Applies : '',
    FormArrayOne: this._fb.array([
      this.initArrayOne(),
    ])
  });
}
public initArrayOne() {
  return this._fb.group({
    OneField: '',
    FormArrayTwo : this._fb.array([
      this.initFormArrayTwo()
    ])
  });
}
public addMarket() {
  const control = <FormArray> this.MaintFormGroup.get('FormArrayOne');
  control.push(this.initArrayOne());
}
public removeMarket(i: number) {
  const control = <FormArray> this.MaintFormGroup.get('FormArrayOne');
  control.removeAt(i);
}
public initFormArrayTwo() {
  return this._fb.group({
    Destination : ''
  });
}
public addFormArrayTwo() {
  const Control = <FormArray> this.MaintFormGroup.get('FormArrayTwo');
  Control.push(this.initFormArrayTwo());
}
public removeFormArrayTwo(j: number) {
  const Control = <FormArray> this.MaintFormGroup.get('FormArrayTwo');
  Control.removeAt(j);
}

Answer 1

This link更多地是解决这个问题的一个要点，但是您可以看看我在stackblitz上创建的这个项目，它有很深的嵌套形式。