register-form.component.html

<form (ngSubmit)="onSignUpSubmit()" #f="ngForm" >


  <div class="row">

    <div class="input-field col s12">
      <input id="email"
             type="email"
             required
             name='email'
             [(ngModel)]="signUpUser.email"
             class="validate">
      <label for="email">Email</label>
    </div>



    <div class="input-field col s12">
      <input id="password"
             type="password"
             required
             name='password'
             [(ngModel)]="signUpUser.password"
             class="validate">
      <label for="password">Password</label>
    </div>



    <div class="input-field col s12">
      <input id="password_confirmation"
             type="password"
             required
             name='password_confirmation'
             [(ngModel)]="signUpUser.passwordConfirmation"
             class="validate">
      <label for="password_confirmation">Password confirmation</label>
    </div>

    <span *ngIf="signUpUser.password != signUpUser.passwordConfirmation"
          style="color:red">
      Passwords must match
    </span>


    <div class="col s12">

      <button type="submit"
              [disabled]="!(f.valid) || !(signUpUser.password == signUpUser.passwordConfirmation)"
              class="waves-effect waves-light btn blue right">
        Sign up
      </button>

    </div>

  </div>


</form>