如何让mat-select验证工作？

<mat-form-field>
  <mat-select placeholder="选择项" [formControl]="myControl" [(ngModel)]="selectedOption">
    <mat-option *ngFor="let option of options" [value]="option.value">{{ option.label }}</mat-option>
  </mat-select>
</mat-form-field>

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

@Component({
  selector: 'app-my-component',
  templateUrl: './my-component.component.html',
  styleUrls: ['./my-component.component.css']
})
export class MyComponent {
  myControl = new FormControl('', Validators.required);
  options = [
    { value: 'option1', label: '选项1' },
    { value: 'option2', label: '选项2' },
    { value: 'option3', label: '选项3' }
  ];
  selectedOption: string;
}

<mat-form-field>
  <mat-select placeholder="选择项" [formControl]="myControl" [(ngModel)]="selectedOption">
    <mat-option *ngFor="let option of options" [value]="option.value">{{ option.label }}</mat-option>
  </mat-select>
  <mat-error *ngIf="myControl.invalid && myControl.touched">请选择一个选项</mat-error>
</mat-form-field>

<button mat-raised-button color="primary" (click)="submitForm()">提交</button>

submitForm() {
  if (this.myControl.valid) {
    // 执行提交操作
  } else {
    // 表单验证未通过，执行相应的操作
  }
}