控制台中的NgModel错误

Question

我正在尝试从此组件中记录ngModel，以便我可以将其检查用于教育目的

<input ngModel name="firstName" id="firstName" type="text" #firstname="ngModel" (change)="log(firstname)" class="form-control">

但我收到此错误，我似乎无法诊断错误。

Uncaught Error: Template parse errors: There is no directive with "exportAs" set to "ngModel" ("">First Name</label>
<input [(ngModel)]="firstName" name="firstName" id="firstName" type="text" 
[ERROR ->]#firstname="ngModel" (change)="log(firstname)" class="form-control 
</div><div class="form-grou"): ng:///AppModule/ContactFormComponent.html@3:79 Can't bind to 'ngModel' 
since it isn't a known property of 

Answer 1

1. 复制您添加的模块代码
2. 删除模块并确保项目使用（ng serve）成功编译。
3. 重新生成模块并放回代码。
4. 在app.modile.ts
中添加FormsModule

@NgModule({
      declarations: [
        AppComponent,
        ContactFormComponent
      ],
      imports: [
        BrowserModule,
        FormsModule
      ],