Angular2嵌套formGroup- formarrays和模板结合

Question

这是问题：

我有一个带有嵌套式组的复杂形式，这是其外观的"简化"结构：

-> MyForm (formGroup)
    -> Whatever01 (formControl - input)
    -> Whatever02 (formControl - input)
    -> WhateverGroup01 (formGroup)
        -> Whatever03 (formControl - input)
        -> Whatever04 (formControl - input)
    -> WhateverArray01 (formArray)
        -> WhateverGroup02 (formGroup)
            -> Whatever05 (formControl - input)
            -> WhateverGroup03 (formGroup)
                -> Whatever06 (formControl - input)
        -> WhateverGroup04 (formGroup)
            -> Whatever07 (formControl - input)
    -> ...

角度，它应该以某种方式看起来像这样(不正确/完整，而只是为了给出一个想法(：

this.myForm = this.fb.group({
    whatever01: ['',Validators.compose([...])],
    whatever02: ['',Validators.compose([...])],
    whateverGroup01: this._formBuilder.group({
        whatever03: ['',Validators.compose([...])],
        whatever04: ['',Validators.compose([...])]
    }),
    whateverArray01: this._formBuilder.array([
        this._formBuilder.group({
            whatever05: ['',Validators.compose([...])],
            whateverGroup03: this._formBuilder.group({
                whatever06: ['',Validators.compose([...])]
            })
        }),
        this._formBuilder.group({
            whatever07: ['',Validators.compose([...])],
        })
    ])
    ...
});

从root myform项目中，事情变得非常好，可以获取formarray，但随后会出现麻烦。...

所以，我只是无法访问" whywhing05"(和06但05不起作用...所以...(formControl将其绑定到模板上！这是模板实际上的样子(意图在数组之前跳过零件(，有趣的部分是[?????] =" ????"，这实际上是问题所在。

<form [formGroup]="myForm" ...>
    <!-- ...skipped... -->
    <div formArrayName="whateverArray01" *ngFor="let item of myForm.controls.whateverGroup01.controls.whateverArray01.controls;let idx = index;" [formGroupName]="idx">
        <div [????]="????">
            <input formControlName="whatever05" ... />
            <div [????]="????">
                <input formControlName="whatever06" ... />
            </div>
        </div>    
    </div>
</form>

位于formarray中的FormGroup具有所有相同的结构。

基本上，问题是我无法访问formgroup中的formcontrols ...

我尝试了几种解决方案，我使用了[FormGroupName]，FormGroupName(无括号(，[FormGroup]，FormControlname，...但是无法弄清楚我必须用来将相应的FormGroup/FormGroup/formgroup/form concontrol与数据 ！

我现在遇到了这种错误：

formGroup expects a FormGroup instance. Please pass one in. 
// This when using [formGroup]="item.whateverGroup02"
Cannot find control with name: 'whatever05'
// When using [formGroup]="item.controls.whateverGroup02"
Cannot find control with path: 'whateverArray01 -> 0 ->'
// This when using [formGroupName]="whateverGroup02"

感谢您的阅读/帮助

这是一个带有一些代码的plunker：

http://plnkr.co/edit/wf7fchmkhiwzmlwlncf8?p=peview

Answer 1

您的表格的构建对我来说似乎是正确的。您在模板中遇到了一些麻烦，FormArray的迭代不正确，您的FormArray不在FormGroup WhateverGroup01内部，因此迭代应该看起来像这样：

*ngFor="let ctrl of myForm.controls.whateverArray01.controls;

关于FormArray的模板部分，应该看起来像这样：

<div *ngFor="let ctrl of myForm.controls.whateverArray01.controls; let i = index" [formGroupName]="i">
   <input formControlName="whatever05" />
   <div formGroupName="whateverGroup03">
      <input formControlName="whatever06" />
   </div>
</div>

应该解决问题：(

这是

demo

Answer 2

首先您的视图具有错误的绑定：

[formGroupName]="whateverGroup02"

组件中没有whateverGroup02属性。我们应该通过以下字符串：

formGroupName="whateverGroup02"

然后，如果您建立了类似：

的组

this.fb.group({
  x: 1,
  y: {
    z: 2
  }
})

您会得到

FormGroup
  -> FormControl with name `x` and value `1`   
  -> FormControl with name `y` and value `{ z: 2 }`

这意味着，如果您想操纵嵌套的形式组，则必须创建它们。即。

let fGroups = data.map(rs => this.buildFormGroup(rs));
...
buildFormGroup(obj) {
  let formGroup: { [id: string]: AbstractControl; } = {};
  Object.keys(obj).forEach(key => {
    formGroup[key] = typeof obj[key] === 'object' ?
      this.buildFormGroup(obj[key]) : 
      new FormControl(obj[key]);
  });
  return this._formBuilder.group(formGroup);
}

plunker示例