angular - 类型脚本错误属性在类型上不存在

Question

我是 angularjs 2 和 ionic 2 的新手。我正在使用带有验证器、FormControl 和 FormGroup 的 angularjs 表单。当我使用 ionic serve --lab 执行项目时，一切都很好。但是当我构建该项目时，它给出了 error: Property 'username' does not exist on type.

登录.ts

import { Component } from '@angular/core';

import { LoadingController, NavController } from 'ionic-angular';

import { AuthService } from '../../service/authService';

import {Validators, FormBuilder, FormGroup, FormControl } from '@angular/forms';

@Component({
  selector: 'page-login',
  templateUrl: 'login.html'
})
export class LoginPage {

  user: any;

  submitAttempt: boolean = false;

  slideTwoForm : FormGroup;

  constructor(public navCtrl: NavController, 
              public authService: AuthService,
              public loadingCtrl: LoadingController, 
              private formBuilder: FormBuilder) {

    this.slideTwoForm = formBuilder.group({
      username: ['', Validators.compose([Validators.minLength(5),          Validators.required])],
      description: ['', Validators.required],
      age: ['']
    });
  }

  logForm() {
    if (!this.slideTwoForm.valid) {
      this.submitAttempt = true;
    }
  }

}

login.html

<ion-content padding>
    <form [formGroup]="slideTwoForm" (ngSubmit)="logForm()" novalidate>
        <ion-item>
            <ion-label floating>Username</ion-label>
            <ion-input #username formControlName="username" type="text"></ion-input>
        </ion-item>
        <ion-item *ngIf="!slideTwoForm.controls.username.valid  && submitAttempt">
            <p>Please enter a valid name.</p>
        </ion-item>
        <ion-item>
          <ion-label>Description</ion-label>
          <ion-textarea formControlName="description"></ion-textarea>
        </ion-item>
        <ion-item>
            <ion-label floating>Age</ion-label>
            <ion-input formControlName="age" type="number"></ion-input>
        </ion-item>
        <ion-item *ngIf="!slideTwoForm.controls.age.valid  && submitAttempt">
            <p>Please enter a valid age.</p>
        </ion-item>
        <button ion-button type="submit">Submit</button>
    </form>
</ion-content>

一切正常，直到我运行ionic build android命令生成apk文件。
有人可以告诉我为什么会收到这些错误吗？

我还引用了这个链接:Property does not exist on type. TypeScript但它帮不了我:

Answer 1

<ion-content padding>
    <form [formGroup]="slideTwoForm" (ngSubmit)="logForm()" novalidate>
        <ion-item>
            <ion-label floating>Username</ion-label>
            <ion-input #username formControlName="username" type="text"></ion-input>
        </ion-item>
        <ion-item *ngIf="!slideTwoForm.controls["username"].valid  && submitAttempt">
            <p>Please enter a valid name.</p>
        </ion-item>
        <ion-item>
          <ion-label>Description</ion-label>
          <ion-textarea formControlName="description"></ion-textarea>
        </ion-item>
        <ion-item>
            <ion-label floating>Age</ion-label>
            <ion-input formControlName="age" type="number"></ion-input>
        </ion-item>
        <ion-item *ngIf="!slideTwoForm.controls["age"].valid  && submitAttempt">
            <p>Please enter a valid age.</p>
        </ion-item>
        <button ion-button type="submit">Submit</button>
    </form>
</ion-content>