Angular报错：ERROR TypeError: control.setParent is not a function

Angular报错：ERROR TypeError: control.setParent is not a function

这里是定义的 myForm ，字段 imageIds 为数组：

myForm = this.fb.group({
    id: [''],
    title: [''],
    content: [''],
    imageIds: this.fb.array(['']),
});

从详情接口取回数据后，填充到表单里的 imageIds 字段里报错。

let imageIds = this.detail.imageIds;
let newIds = this.myForm.get('imageIds') as FormArray;
if (imageIds) {
  let key : any;
  for(key in imageIds) { 
    // <-- ERROR TypeError: control.setParent is not a function
    newIds.push(imageIds[key]); 
  }
} 

this.noteForm.patchValue({
          id: this.detail.id,
          title: this.detail.title,
          imageIds: newIds.value, // <----  补充数据
 });

错误原因： newIds 是表单组件里的 FormArray 格式，因此push进去的值也应该是 FormControl 格式。
使用 new FormControl(imageIds[key]) 即可。

let imageIds = this.detail.imageIds;
let newIds = this.myForm.get('imageIds') as FormArray;
if (imageIds) {
  let key : any;
  for(key in imageIds) { 
    // <-- 使用 new FormControl() 
    newIds.push(new FormControl(imageIds[key])); 
  }
} 

this.noteForm.patchValue({
          id: this.detail.id,
          title: this.detail.title,
          imageIds: newIds.value, // <----  补充数据
 });

参考内容：

https://blog.youkuaiyun.com/u011763994/article/details/78682576
https://stackoverflow.com/questions/51209125/control-setparent-is-not-a-function-when-dymanically-creating-formgroup

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