如果字段为空，则angular form禁用提交按钮

<form #myForm="ngForm">
  <input type="text" name="myField" [(ngModel)]="myField" required>
  <button type="submit" [disabled]="!myForm.valid">提交</button>
</form>

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

@Component({
  selector: 'app-my-form',
  templateUrl: './my-form.component.html',
  styleUrls: ['./my-form.component.css']
})
export class MyFormComponent {
  myForm: FormGroup;

  constructor() {
    this.myForm = new FormGroup({
      myField: new FormControl('', Validators.required)
    });
  }
}

<button type="submit" [disabled]="!myForm.valid">提交</button>