import – Angular2教程(英雄之旅)：找不到模块’angular2-in-me

app/main.ts(5,51): error TS2307: Cannot find module ‘angular2-in-memory-web-api’.

(Visual Studio Code给我在main.ts中的相同的错误 – 红色波浪下划线。)

这里是我的systemjs.config.js：

/**
 * System configuration for Angular 2 samples
 * Adjust as necessary for your application needs.
 */
(function(global) {
  // map tells the System loader where to look for things
  var map = {
    'app':                        'app',// 'dist','@angular':                   'node_modules/@angular','angular2-in-memory-web-api': 'node_modules/angular2-in-memory-web-api','rxjs':                       'node_modules/rxjs'
  };
  // packages tells the System loader how to load when no filename and/or no extension
  var packages = {
    'app':                        { main: 'main.js',defaultExtension: 'js' },'rxjs':                       { defaultExtension: 'js' },'angular2-in-memory-web-api': { defaultExtension: 'js' },};
  var ngPackageNames = [
    'common','compiler','core','http','platform-browser','platform-browser-dynamic','router','router-deprecated','upgrade',];
  // Add package entries for angular packages
  ngPackageNames.forEach(function(pkgName) {
    packages['@angular/'+pkgName] = { main: pkgName + '.umd.js',defaultExtension: 'js' };
  });
  var config = {
    map: map,packages: packages
  }
  System.config(config);
})(this);

这里是我的应用程序/ main.ts：

// Imports for loading & configuring the in-memory web api
import { provide }    from '@angular/core';
import { XHRBackend } from '@angular/http';

import { InMemoryBackendService,SEED_DATA } from 'angular2-in-memory-web-api';
import { InMemoryDataService }               from './in-memory-data.service';

// The usual bootstrapping imports
import { bootstrap }      from '@angular/platform-browser-dynamic';
import { HTTP_PROVIDERS } from '@angular/http';

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

bootstrap(AppComponent,[
    HTTP_PROVIDERS,provide(XHRBackend,{ useClass: InMemoryBackendService }),// in-mem server
    provide(SEED_DATA,{ useClass: InMemoryDataService })     // in-mem server data
]);