Question

我是Angular（7+）的新手，在引导选择下拉列表中选择新值时，似乎无法触发selectionChange事件。

是否缺少某些内容或需要的语法？

我也尝试了（change）和（ngModelChange），但还是没有。而且控制台中没有错误...

这是我的HTML和组件方法

  
import {BsDatepickerConfig} from 'ngx-bootstrap';

@Component({
  selector: 'app-register',
  templateUrl: './register.component.html',
  styleUrls: ['./register.component.css']
})
export class RegisterComponent implements OnInit {
  @Output() cancelRegister = new EventEmitter();
  user: User;
  registerForm: FormGroup;
  bsConfig: Partial < BsDatepickerConfig > ;
  emailErrorMessage: string;
  userErrorMessage: string;
  currentYear: number = new Date().getFullYear();
  startYear = this.currentYear - 120;
  years: number[] = [];
  months: string[] = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
  countryList = new Countries().countryCode;
  inputCity: string;


  constructor(private authService: AuthService, private router: Router,
    private alertify: AlertifyService, private fb: FormBuilder) {
    for (let i = this.currentYear; i > this.startYear; i--) {
      this.years.push(i);
    }
  }

  ngOnInit() {
    this.bsConfig = {
      containerClass: 'theme-red'
    };
    this.createRegisterForm();
  }

  onCountryChange(countryObj) {
    let test = 0;
  }

  onCityChange(cityObj) {
    let i = 0;
  }
 ...

}

<div class="form-group">
  <select (selectionChange)="onCountryChange($event)" id="country" class="form-control">
    <option *ngFor="let country of countryList" [value]="country.code" [selected]="country.name == 'United States'">
      {{country.name}}
    </option>
  </select>
</div>

Answer 1

您可以改用(change)="onCountryChange($event)"

Answer 2

尝试（ngModelChange）=“ onCountryChange（$ event）”

selectionChange在Angular 7中不触发

2 个答案: