如何在Angular2模板文件中引用外部定义的常量

export const API_URL = 'https://api.example.com';
export const MAX_RESULTS = 10;

import { Component } from '@angular/core';
import { API_URL, MAX_RESULTS } from './constants';

@Component({
  selector: 'app-root',
  template: `
    <h1>API URL: {{ apiUrl }}</h1>
    <h2>Max Results: {{ maxResults }}</h2>
  `
})
export class AppComponent {
  apiUrl = API_URL;
  maxResults = MAX_RESULTS;
}

<h1>API URL: {{ apiUrl }}</h1>
<h2>Max Results: {{ maxResults }}</h2>