如何在不使用服务的情况下在子组件和父组件之间传递反应式表单数据

当我们单击父级按钮时，我们希望使用来自父级的子级反应式表单数据。目前我们正在使用 viewchild 来获取子组件引用。我们正在获取所有静态数据，但没有获取表单填充的数据....................................... ...................................................... ............

parent.component.ts
@ViewChild(DetailsComponent) childrenComponent: childrenComponent;

save(){
let model=this.childrenComponent.buildDetailsModel();
/*here api to save model*/
}
children.component.ts
buildDetailsModel(): Details {
var a = {
  reportedToId: this.detailsForm.get('reportedTo').value,
  reportedOn: this.detailsForm.get('reportedTime').value,
  identifiedById: this.detailsForm.get('identifiedBy').value,
  identifiedOn: this.detailsForm.get('dateAndTimeIdentified').value,
  locationTypeId: this.detailsForm.get('locationType').value,
  addressId: this.detailsForm.get('locationAddress').value,
  AddressLine: this.detailsForm.get('locationOfAddress').value,
  description: this.detailsForm.get('description').value,
  PeopleExposed: this.dataSource
  };
  return a;
}

parent.html 
<child></child>

child.html
<form [formGroup]="detailsForm">
  <div fxLayout="column wrap" fxLayoutGap="12px">

    <div fxLayout="column" fxLayout.lt-sm="column" fxLayout.lt-md="column" 
   fxLayoutGap="24px">

      <div fxFlex="row" fxLayoutGap="24px" fxLayout.lt-md="column">
        <div fxFlex="column">
          <mat-form-field>
            <mat-label>Reported To</mat-label>
            <mat-select matInput formControlName="reportedTo">
              <mat-option value="Test 1">Test 1</mat-option>
              <mat-option value="Test 2">Test 1</mat-option>
            </mat-select>
          </mat-form-field>


          <mat-form-field>
            <input matInput [matDatepicker]="reportedTime" placeholder="Date 
          and time reported" date="true" time="true" 
          formControlName="reportedTime">
            <mat-datepicker-toggle matSuffix [for]="reportedTime"></mat- 
           datepicker-toggle>
            <mat-datepicker #reportedTime></mat-datepicker>
          </mat-form-field>

          <mat-form-field>
            <mat-label>Identified by</mat-label>
            <mat-select matInput formControlName="identifiedBy">
              <mat-option value="Test 1">Test 1</mat-option>
              <mat-option value="Test 2">Test 1</mat-option>
            </mat-select>
          </mat-form-field>
        </div>

将子表单包裹在表单元素内，以便您可以从父表单提交子表单，然后在子组件中注入 FormGroupDirective 以获取父表单的引用

<form (ngSubmit)="save()" [formGroup]="detailsForm"> 
    <app-child></app-child>
    <button type="button">Save</button>
 </form>

然后使用controlContainer在子组件中提供现有的FormGroupDirective

子组件.ts

  form;
  constructor(private fb: FormBuilder, @Host() private parentFor: FormGroupDirective) { }

  ngOnInit() {
    this.form = this.parentFor.form;
    //Add FormControl as per your need
    this.form.addControl('child', this.fb.group({
      name: "",
      email: ""
    }))

  }

子组件.html

<form formGroupName="child">
  <input formControlName="name">
  <input formControlName="email">
</form>

Example:https://stackblitz.com/edit/angular-xusdev