角2表单元素作为组件-验证无效

Question

我对我的项目http://blog.rangle.io/angular-2-ngmodel-and-custom-form-components/实施了此解决方案，基本上，您使用表单元素构建了一个组件并将其放入表单中，我遇到的问题是当我想建立一个验证器来检查字段之间的依赖关系时

import {Directive, Attribute} from '@angular/core';

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

    @Directive({
      selector: '[validateEqual][ngModel]',
      providers: [
        {provide: NG_VALIDATORS, useExisting: ParentFieldNotNullValidator, multi: true}
      ]
    })
    export class ParentFieldNotNullValidator {
      constructor(@Attribute('validateEqual') public validateEqual: string) {
      }

      validate(c: AbstractControl): {[key: string]: any} {
        if (!c.value) {
           return null;
        }
        let e = c.root.get(this.validateEqual);

        if (e && e.value) {
          console.log('ERROR 1');
          return null;
        }
        console.log('error 2');
        return {validateError: "message"} }}

以常规模板驱动的形式工作，但在此实现中却没有，我从webbrowser获得了这种流截图

当父字段存在且不为null时，此验证器应仅写入“ ERROR 1”

我做错了什么？ 我的html：

<form #form="ngForm" (ngSubmit)="onSubmit(form.value)">
  <div class="u-space-bottom-8">
    <form-input
      cannotContainSpace
      minlength="4"
      required
      name="username"
      [(ngModel)]="user.username">
      >
    </form-input>
  </div>
  <div class="u-space-bottom-8">
    <form-input
      validateEqual="username"
      type="password"
      required
      name="password"
      [(ngModel)]="user.password">
      >
    </form-input>
  </div>
  <button
    class="c-btn c-btn--default u-h-10 u-bg-gray-16 u-paint-white-1"
    type="send"
    [disabled]="!form.valid"
  >
    {{'btn_login'|translate}}
  </button>
</form>

Answer 1

我找到了一个解决方案，问题是数据绑定，现在我的验证器看起来像这样：

import {Directive, Input} from '@angular/core';

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

@Directive({
  selector: '[validateEqual][ngModel]',
  providers: [
    {provide: NG_VALIDATORS, useExisting: ParentFieldNotNullValidator, multi: true}
  ]
})
export class ParentFieldNotNullValidator {
  constructor() {
  }
  @Input('validateEqual') parentValue: string;
  validate(c: AbstractControl): {[key: string]: any} {
    if (!c.value) {
      return null;
    }
    if (this.parentValue) {
      return null;
    }
    return {parentFieldNotNull: "message"}
  }
}

和HTML看起来像这样

<form #form="ngForm" (ngSubmit)="onSubmit(form.value)">
  <div class="u-space-bottom-8">
    <form-input
      cannotContainSpace
      minlength="4"
      required
      name="username"
      [(ngModel)]="user.username">
      >
    </form-input>
  </div>
  <div class="u-space-bottom-8">
    <form-input
      [validateEqual]="user.username"
      type="password"
      required
      name="password"
      [(ngModel)]="user.password">
      >
    </form-input>
  </div>
  <button
    class="c-btn c-btn--default u-h-10 u-bg-gray-16 u-paint-white-1"
    type="wyslij"
    [disabled]="!form.valid"
  >
    {{'btn_login'|translate}}
  </button>
</form>