Angular 2 APP_INITIALIZER执行顺序/异步问题

import { Injectable } from '@angular/core';

@Injectable()
export class AppConfigService {
  private config: any;

  load(): Promise<any> {
    // 在这里加载配置信息，可以是从服务器获取或从本地文件读取
    return new Promise((resolve, reject) => {
      // 模拟异步加载配置信息
      setTimeout(() => {
        this.config = {
          // 配置信息
        };
        resolve();
      }, 2000);
    });
  }

  getConfig(): any {
    return this.config;
  }
}

import { NgModule, APP_INITIALIZER } from '@angular/core';
import { AppConfigService } from './app-config.service';

export function initializeApp(appConfigService: AppConfigService) {
  return () => appConfigService.load();
}

@NgModule({
  // ...
  providers: [
    AppConfigService,
    {
      provide: APP_INITIALIZER,
      useFactory: initializeApp,
      deps: [AppConfigService],
      multi: true
    }
  ],
  // ...
})
export class AppModule { }