angular中的自定义验证

import { AbstractControl, ValidationErrors } from '@angular/forms';

export function passwordValidator(control: AbstractControl): ValidationErrors | null {
  const password: string = control.value;
  const hasUppercase = /[A-Z]/.test(password);
  const hasLowercase = /[a-z]/.test(password);
  const hasNumber = /\d/.test(password);
  const hasSpecialCharacter = /[!@#$%^&*()_+\-=\[\]{};':"\\|,.<>\/?]+/.test(password);
  const valid = hasUppercase && hasLowercase && hasNumber && hasSpecialCharacter;

  if (!valid) {
    return { 'passwordComplexity': true };
  }

  return null;
}

<form [formGroup]="myForm">
  <input type="password" formControlName="password" />
  <div *ngIf="myForm.get('password').hasError('passwordComplexity')">
    Password must contain at least one uppercase letter, one lowercase letter, one number, and one special character.
  </div>
</form>

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

@Component({
  selector: 'app-my-component',
  template: '...',
})
export class MyComponent {
  myForm: FormGroup;

  constructor(private fb: FormBuilder) {
    this.myForm = this.fb.group({
      password: ['', [Validators.required, passwordValidator]],
    });
  }
}