如何使用angular2设置验证器不接受索引0的选定选项

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

@Component({
  selector: 'app-my-component',
  template: `
    <form [formGroup]="myForm">
      <select formControlName="mySelect">
        <option value="0">Option 0</option>
        <option value="1">Option 1</option>
        <option value="2">Option 2</option>
      </select>
    </form>
  `
})
export class MyComponent {
  myForm: FormGroup;

  constructor() {
    this.myForm = new FormGroup({
      mySelect: new FormControl('', [this.validateSelectedOption])
    });
  }

  validateSelectedOption(control: FormControl) {
    if (control.value === '0') {
      return { invalidOption: true };
    }
    return null;
  }
}

@Component({
  selector: 'app-my-component',
  template: `
    <form [formGroup]="myForm">
      <select formControlName="mySelect">
        <option value="0">Option 0</option>
        <option value="1">Option 1</option>
        <option value="2">Option 2</option>
      </select>
      <div *ngIf="myForm.get('mySelect').hasError('invalidOption')">
        Please select a valid option.
      </div>
    </form>
  `
})
export class MyComponent {
  // ...
}