我在Angular 版本10中使用了React形式。但是得到了以下错误。

ERROR Error: formGroup expects a FormGroup instance. Please pass one in.

       Example:

       
    <div [formGroup]="myGroup">
      <input formControlName="firstName">
    </div>

    In your class:

    this.myGroup = new FormGroup({
       firstName: new FormControl()
    });
    at Function.missingFormException (forms.js:1700:1)
    at FormGroupDirective._checkFormPresent (forms.js:5632:1)
    at FormGroupDirective.ngOnChanges (forms.js:5454:1)
    at FormGroupDirective.rememberChangeHistoryAndInvokeOnChangesHook (core.js:2373:1)
    at callHook (core.js:3285:1)
    at callHooks (core.js:3251:1)
    at executeInitAndCheckHooks (core.js:3203:1)
    at selectIndexInternal (core.js:6324:1)
    at ɵɵadvance (core.js:6306:1)
    at PatientInformationComponent_Template (template.html:39:34)

我的示例HTML代码如下所示。

<div [formGroup]="MyForm">
      <input formControlName="firstName">
      <input formControlName="lastName">
</div>

我的TS代码：

export class MyComponent implements OnInit{
   MyForm: FormGroup;

   constructor( private formbuilder: FormBuilder) {}

   ngOnInit() {
       this.MyForm= this.formbuilder.group({
        firstName: new FormControl("", Validators.maxLength(100)),
        lastName: new FormControl("",Validators.maxLength(100)),
    });
   }

}

虽然表单工作正常，但是错误总是显示在控制台上。我想这可能是因为一些其他的生命周期钩子。你能给予我一些解决这个问题的方法吗？