角度4:将属性“推"为和“控件"在类型"AbstractControl"上不存在 [英] Angular 4: Property "push" and "controls" does not exist on type "AbstractControl"

问题描述

我已通过此链接实现了代码 http://plnkr.co/edit/yV94ZjypwBgHAlb0RLK2? p = preview ，但出现推送并控制错误.

I was implemented the code from this link http://plnkr.co/edit/yV94ZjypwBgHAlb0RLK2?p=preview but getting push and controls error.

这是我所做的，并且不知道这是怎么回事.

Here is what i did and don't know what is wrong with it.

import { Component } from '@angular/core';
import { ViewController,Platform } from 'ionic-angular';
import { FormBuilder,FormGroup,Validators,FormControl,FormArray } from '@angular/forms';

@Component({
  selector: 'filter-vendor',
  templateUrl: 'filter-vendor.html'
})

export class FilterVendorPage {




  questions = [{id:1,text:'Question 1', answers:[{id:1},{id:2}]},{id:2,text:'Question 2', answers:[{id:11},{id:22}]}]
  surveyForm:FormGroup;



  constructor(
    private viewCtrl: ViewController, 
    private formBuilder:FormBuilder
     ){


      this.surveyForm=this.formBuilder.group({
        question:formBuilder.array([])
      })

      for(var i=0;i<this.questions.length;i++){
          let question=formBuilder.group({
            question_id:[this.questions[i].id,Validators.required],
            answer_id:formBuilder.array([])
          });
          this.surveyForm.controls['questions'].push(question);
      }
}


   onChange(id, isChecked, index) {

    const answers = <FormArray>this.surveyForm.controls.questions.controls[index].controls.answer_ids

    if(isChecked) {
          answers.push(new FormControl(id))
        } else {
          let idx = answers.controls.findIndex(x => x.value == id)
          answers.removeAt(idx)
    }
  }

}

请帮助我解决此问题.非常感谢

Please help me to resolve this issue.Lot's of thanks

推荐答案

Typescript抱怨类型检查.您需要将控件转换为FormArray.所以改变

Typescript complains on type checking. You need to cast your control to FormArray. So change

1)

this.surveyForm.controls['questions'].push(question);

到

(<FormArray>this.surveyForm.controls['questions']).push(question);

或

(this.surveyForm.controls['questions'] as FormArray).push(question);

或

(this.surveyForm.get('questions') as FormArray).push(question);

2)

const answers = <FormArray>this.surveyForm.controls.questions.controls[index].controls.answer_ids

到

const answers = this.surveyForm.get(['questions', index, 'answer_ids']) as FormArray;

或

const answers = this.surveyForm.get(`questions.${index}.answer_ids`) as FormArray;

分叉柱塞

Forked Plunker

这篇关于角度4:将属性“推"为和“控件"在类型"AbstractControl"上不存在的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！