错误：在Angular2中找不到“未定义”的NgModule元数据

Question

请在下面找到我的代码，当我在下面添加内容时就开始遇到此问题

platformBrowserDynamic().bootstrapModule(AppModule);

app.module.ts

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { FormsModule } from '@angular/forms';
import { HttpModule } from '@angular/http';

import { AppComponent } from './app.component';

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

app.component.ts

import { Component } from '@angular/core';
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { AppModule } from './app.module';
import { HTTPUserService } from "./app.service";

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css'],
  providers: [HTTPUserService]
})
export class AppComponent {
  title = 'app works!';
  getData:string;

  constructor(private _httpService:HTTPUserService){}

  onGet() {
    this._httpService.getUserData()
        .subscribe(
            data => this.getData = data,
            error => alert(error),
            () => console.log("Finished!")
        );
  }
}

platformBrowserDynamic().bootstrapModule(AppModule);

Answer 1

为什么要在组件中引导应用程序？ 在外部文件中执行此操作。 通常，这是在main.ts文件中完成的，该文件仅知道AppModule的存在，仅此而已