正在获取嵌套formArray中的控件

Question

我很想知道如何在嵌套的formArray中获取控件。我初始化了此表单

ngOnInit(): void {
this.surveyForm = this.formBuilder.group({
'surveyTitle': [null],
'surveyDescription': new FormControl(null),
'questionsDetail': this.formBuilder.array([
this.formBuilder.group({
'questionType': new FormControl('mcq'),
'question': new FormControl(null),
'choices': this.formBuilder.array([])
})
])
});

但是当我试图访问我的选择formArray的控件时，我得到了一个错误。我用了这个代码

get questionsDetailcontrols() {
return (this.surveyForm.get('questionsDetail') as FormArray).controls;
}
get choicesControl()
{
return (this.questionsDetailcontrols.get('choices') as FormArray).controls;
}

我在get("choices"(中得到一个错误，指出"；类型"AbstractControl[]"上不存在属性"get"；。有人能告诉我如何访问嵌套数组中的控件吗。

提前感谢

Answer 1

试试这个。

get questionsDetailcontrols() {
return this.surveyForm.get('questionsDetail') as FormArray;
}
getChoicesControl(index: number)
{
return (this.questionsDetailcontrols.at(index).get('choices') as FormArray).controls;
}