Angular: 没有将 "exportAs" 设置为 "ngForm" 的指令时出错

Angular: Error no directive with "exportAs" set to "ngForm"

我已经尝试导入 FormsModule 和 NgForm 模块以及将 FormsModule 添加到导入数组。

下面是我的代码:

//our root app component
import { Component, NgModule, VERSION } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import {FormsModule, NgForm} from '@angular/forms';

@Component({
  selector: 'my-app',
  template: `
  <form #searchForm="ngForm">
  <input type="text" required [(ngModel)]="model.search" ngControl="search" #inputSearch="ngForm">
  <p class="error" [hidden]="inputSearch.valid"> This input is required</p>


  </form>

  `,
  styles: [`
  .error {
    color: red;
    font-size: 11px;
  }
  `]
})
export class App {
  public model = {
    search: "" 
  }

  constructor() {

  }
}

@NgModule({
  imports: [BrowserModule, FormsModule],
  declarations: [App],
  bootstrap: [App],
})
export class AppModule {}

下面是错误打印输出:

runtime.9ff156e16d788666a54a.js:16 Error: Template parse errors: There is no directive with "exportAs" set to "ngForm" (" ]#searchForm="ngForm"> ]#inputSearch="ngForm"> This input is required

"): ng:///AppModule/App.html@2:76 Can't bind to 'ngModel' since it isn't a known property of 'input'. (" ][(ngModel)]="model.search" ngControl="search" #inputSearch="ngForm"> https://run.plnkr.co/rhpwnL6UIQwCFOKZ/src/main.js Loading https://run.plnkr.co/rhpwnL6UIQwCFOKZ/src/main.js f @ runtime.9ff156e16d788666a54a.js:16

错误是由这一行引起的:

#inputSearch="ngForm"

这是正确的行:

#inputSearch="ngModel"

这是工作示例。当您在表单标签中使用 ngModel 时,您还需要为 "name" 属性提供值。

  <form #searchForm="ngForm">
  <input type="text" required name="search" [(ngModel)]="model.search"  #inputSearch="ngModel">
  <p class="error" [hidden]="inputSearch.valid"> This input is required</p>
  </form>