除非开始日期早于angular表单的结束日期，否则禁用提交按钮

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

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

  constructor(private fb: FormBuilder) {
    this.form = this.fb.group({
      startDate: ['', Validators.required],
      endDate: ['', Validators.required]
    });
  }
}

<form [formGroup]="form">
  <label for="startDate">开始日期</label>
  <input type="date" id="startDate" formControlName="startDate">

  <label for="endDate">结束日期</label>
  <input type="date" id="endDate" formControlName="endDate">

  <button type="submit" [disabled]="!form.valid || startDate.value >= endDate.value">提交</button>
</form>