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如何将params传递给异步验证器进行无功角度控制？

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问题，

我使用相同的组件进行读取/编辑例程 . async-validator 与新条目完美配合 . 如果用户意外更改了值并尝试恢复为保存的值，则问题开始 . 我当前的代码将无论如何运行并返回现有的值 . 我想传递更多数据和控制值，以便我可以验证该对值是否已经存在 .

我发布相关代码，

这是我的 form control ，

patientEmail: new FormControl(
    null,
    [Validators.email, Validators.required],
    FormControlValidator.createEmailAsyncValidator(
      this.asyncValidatorService
    ),
  ),

我的异步验证器创建者类是，

export class FormControlValidator {
  static createEmailAsyncValidator(asyncValidatorService: AsyncValidationService) {
    return (control: AbstractControl) => {
      if (!control.pristine) {
        control.markAsPristine();
        return asyncValidatorService
          .validateEmailNotTaken(control)
          .map((response: HttpResponse<boolean>) => {
            return !response.body ? null : { taken: true };
          });
      }
      return Observable.of(null);
    };
  }

最后我的服务，

@Injectable()
export class AsyncValidationService {
  constructor(private httpService: HttpClientService) {}

  public validateEmailNotTaken(control: AbstractControl) {
    return this.httpService.getRequest(
      'PatientsRegistration/IsPatientEmailExist?email=' + control.value,
    );
  }
}

我希望能够将另一个参数传递给我的 createEmailAsyncValidator ，如果可能的话，就像表单中的另一个控件值 .

angular angular-reactive-forms angular-validation

2 回答

  • 0

    如果需要基于另一个控件验证控件，则需要将验证器提升到父控件 . 以下是验证器是否以人名（另一个控件值）开头的验证器示例 .

    app.component.ts

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

const personalEmailValidator: ValidatorFn = (ctrl: FormGroup) => {
  const email = ctrl.get('email') as FormControl;
  const name = ctrl.get('name') as FormControl;

  const valid = (email.value || '').startsWith(name.value);

  return valid ? null : { personalEmailError: 'Email must start with a person name'}
}

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

  form: FormGroup;

  constructor(private fb: FormBuilder) {
    this.form = this.fb.group({
      email: [null],
      name: [null]
    }, { validator: personalEmailValidator })
  }
}

    app.component.html

    <input [formControl]="form.get('name')" placeholder="name" />
<input [formControl]="form.get('email')" placeholder="email" />

{{ form.hasError('personalEmailError') ? form.getError('personalEmailError') : 'form is valid'}}

    Live demo

    回复于
  • 1

    所以我以另一种方式工作，受到Tomasz Kula answer的启发

    我创建了一个实现 AsyncValidator 接口的Async Directive ，我将额外的params作为`对象传递，在我的例子中它看起来像这样，

    {
 coupledControl: AbstractControl,
 method: {
          apiUrl: string
         }
}

    这是我的 directive 代码，

    import { Directive, forwardRef, Input } from '@angular/core';
import { NG_ASYNC_VALIDATORS, Validator, AbstractControl } from '@angular/forms';
import { Observable } from 'rxjs/Observable';
import { HttpClientService } from '../../../../../shared/services/httpclient.service';
import { HttpResponse } from '@angular/common/http';
import { IAsyncMethod } from './../interfaces/async-methods-interface';


@Directive({
  // tslint:disable-next-line:directive-selector
  selector: '[asyncValidator][formControlName], [asyncValidator][ngModel]',
  providers: [
    {
      provide: NG_ASYNC_VALIDATORS,
      useExisting: forwardRef(() => AsynValidatorDirective),
      multi: true,
    },
  ],
})
export class AsynValidatorDirective implements Validator {
  @Input() asyncValidator: { coupledControl: AbstractControl; method: IAsyncMethod };

  validate(
    control: AbstractControl,
  ): Promise<{ [key: string]: any }> | Observable<{ [key: string]: any }> {
    return this.validateIsExistAsync(control);
  }

  constructor(private httpService: HttpClientService) {}
  validateIsExistAsync(control: AbstractControl) {
    if (!control.pristine) {
      const coupledControl: AbstractControl = this.asyncValidator.coupledControl;
      const method: IAsyncMethod = this.asyncValidator.method;
      return this.httpService
        .getRequest(method.apiUrl + '?control=' + control.value + '&id=' + coupledControl.value)
        .map((response: HttpResponse<boolean>) => {
          return !response.body ? null : { asyncInvalid: true };
        });
    }
    return Observable.of(null);
  }
}

    在我 HTML ，

    <input [asyncValidator]="{coupledControl: patientRestrationForm.get('patientFileId'), method: this.asyncMethods.validatePatientEmail }" [errorStateMatcher]="matcher" matInput autocomplete="off" formControlName="patientEmail">

    在我的后端，我检查存在和匹配，简单的逻辑！

    会欣赏任何输入，

    回复于

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