angular - formGroup 需要一个 FormGroup 实例

Question

我在 Plunkr 上有一个 Angular 2 RC4 基本表单示例，它似乎抛出以下错误(在 Chrome DEV 控制台中)

这是笨蛋

https://plnkr.co/edit/GtPDxw?p=preview

错误:

browser_adapter.ts:82 EXCEPTION: Error: Uncaught (in promise): EXCEPTION: Error in ./App class App - inline template:1:7
ORIGINAL EXCEPTION: formGroup expects a FormGroup instance. Please pass one in.
           Example: <form [formGroup]="myFormGroup">

ORIGINAL STACKTRACE:
Error: formGroup expects a FormGroup instance. Please pass one in.
           Example: <form [formGroup]="myFormGroup">

    at new BaseException (https://npmcdn.com/@angular/forms@0.2.0/src/facade/exceptions.js:27:23)
    at FormGroupDirective._checkFormPresent (https://npmcdn.com/@angular/forms@0.2.0/src/directives/reactive_directives/form_group_directive.js:110:19)
    at FormGroupDirective.ngOnChanges (https://npmcdn.com/@angular/forms@0.2.0/src/directives/reactive_directives/form_group_directive.js:39:14)
    at DebugAppView._View_App0.detectChangesInter

Answer 1

您的代码中存在一些问题

• <div [formGroup]="form">在 <form> 之外标签
• <form [formGroup]="form">但包含 FormGroup 的属性名称是loginForm因此它应该是<form [formGroup]="loginForm">
• [formControlName]="dob"它传递属性值 dob这是不存在的。您需要传递字符串 dob喜欢[formControlName]="'dob'"或更简单 formControlName="dob"

Plunker example