我想使用表单验证器，但我不知道具体如何使用，我试图同时设置max-length和required的验证，但我不能，而且我已经找过了，但什么也没找到
下面是我尝试做的事情：

import { literalMap } from '@angular/compiler';
import { Component, OnInit } from '@angular/core';
// import {FormsModule, ReactiveFormsModule} from '@angular/forms'
// import { FormControl } from '@angular/forms';
import { FormGroup, FormControl } from '@angular/forms';
import { Validators } from '@angular/forms';
@Component({
  selector: 'app-form',
  templateUrl: './form.component.html',
  styleUrls: ['./form.component.scss']
})
export class FormComponent implements OnInit {
  profileForm = new FormGroup({
    firstName: new FormControl('',Validators.maxLength(1), Validators.required),
    email: new FormControl('',Validators.email),
  });
  constructor() { }

  ngOnInit(): void {
  }
  onSubmit() {
    // TODO: Use EventEmitter with form value
    console.warn(this.profileForm.value);
  }
  testForm(){
    let a = this.profileForm.get('email').valid
    if (a){
      alert('jalo')
    }
  }
  save(){
    let email = this.profileForm.get('email').value
    if(email != '' ){
      alert('jalo')
    }
  }

}