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angular javascript typescript angular-material2

javascript - 如何使用mat-checkbox进行验证?

发布于 2020-03-27 16:06:20

我想知道如何检查该复选框是否被选中,如果未选中,则会为用户显示一条错误消息。我设法放置了错误消息,但无法将其与表单的其余部分一起使用。你能帮助我吗?这就是我要做的。

<mat-checkbox class="hcs-full-width" [formControl]="termsFormControl"> Aceite os termos de uso

</mat-checkbox>
<mat-error *ngIf="termsFormControl.hasError('required')">
    Termo é
    <strong>requirido</strong>
</mat-error>

.ts

export class AppComponent implements OnInit {

  private subscription: Subscription;
  uri: string;
  ssid: string;
  sessiondId: string;
  ip: string;
  mac: string;
  ufi: string;
  mgmtBaseUrl: string;
  clientRedirectUrl: string;
  req: string;
  userName: string;
  hmac: string;

  name: string;
  email: string;

  constructor(@Inject(DOCUMENT) private document: any, private route: ActivatedRoute) {
  }

  ngOnInit() {
    this.route.queryParams
      .filter(params => params.mac)
      .subscribe(params => {
        console.log(params);

        this.ssid = params.ssid;
        this.sessiondId = params.sessionId;
        this.ip = params.ip;
        this.mac = params.mac;
        this.ufi = params.ufi;
        this.mgmtBaseUrl = params.mgmtBaseUrl;
        this.clientRedirectUrl = params.clientRedirectUrl;
        this.req = params.req;
        this.hmac = params.hmac;
      });
      console.log("LOGAR: " + this.nameFormControl.valid);
    console.log("LOGAR: " + this.termsFormControl.valid);
  }

  Logar() {
    if (this.nameFormControl.valid && this.emailFormControl.valid && this.termsFormControl.valid) {
      this.userName = this.name + ";" + this.email;
      this.uri = "#" + this.ssid + "&sessionId=" + this.sessiondId + "&ip=" + this.ip + "&mac=" + this.mac + "&ufi=" + this.ufi + "&mgmtBaseUrl=" + this.mgmtBaseUrl + "&clientRedirectUrl=" + this.clientRedirectUrl + "&req=" + this.req + "&username=" + this.userName + "&hmac=" + this.hmac;
      // console.log("LOGAR: " + this.nameFormControl.valid);
      this.document.location.href = this.uri;
    }
    console.log("LOGAR: " + this.nameFormControl.valid);
    console.log("LOGAR: " + this.termsFormControl.valid);
  };

  emailFormControl = new FormControl('', [
    Validators.required,
    Validators.email,
  ]);

  nameFormControl = new FormControl('', [
    Validators.required,
  ]);

  termsFormControl = new FormControl('', [
    Validators.required,
  ]);

}

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提问者
Marck
被浏览
150
kat1330 2019-01-04 04:00

Checkbox不能那样工作,您必须实现自定义验证程序并将其分配给termsFormControl在您的情况下,它将是:

termsFormControl = new FormControl('', [(control) => {    
    return !control.value ? { 'required': true } : null;
  }]
);

在这里,自定义验证器会明确检查控件的值,如果为false,则将requirederror设置为true这样,您可以将状态设置为表单,并可以使用强大的功能。

请参阅GitHub上的以下问题以获取更多解释,为什么您必须实施自定义验证。

编辑1

要在单击按钮时显示错误消息,您可以将条件设​​置为在复选框无效且脏时增加错误:

<mat-error *ngIf="termsFormControl.invalid && termsFormControl.dirty">
        Termo é <strong>requirido</strong>
</mat-error>

然后在按钮上单击,您可以将复选框设置为脏(我看不到您的完整代码,但是应该是这样的):

onSubmit() {
  this.form.get('termsFormControl ').markAsDirty();
}

编辑2

基于@Julida,内置的验证器 建议Validators.requiredTrue可用于复选框元素。它确认是否选中了复选框。如果未选中,则将控件标记为无效。