Iterating an Object like Array

import {Component} from 'angular2/core';
declare var Symbol;
@Component({
    selector: 'my-app',
    template:`<div>
    <h4>Iterating an Object using Typescript Symbol</h4><br>
Object is : <p>{{obj | json}}</p>
</div>
============================<br>
Iterated object params are:
<div *ngFor="#o of obj">
{{o}}
</div>

`
})
export class AppComponent {
  public obj: any = {
    "type1": ["A1", "A2", "A3","A4"],
    "type2": ["B1"],
    "type3": ["C1"],
    "type4": ["D1","D2"]
  };

  constructor() {
    this.obj[Symbol.iterator] =  () => {
          let i =0;

          return {
            next: () => {
              i++;
              return {
                  done: i > 4?true:false,
                  value: this.obj['type'+i]
              }
            }
          }
    };
  }
}

import {bootstrap}    from 'angular2/platform/browser'
import {AppComponent} from './app.component'

bootstrap(AppComponent);

beforeEach(() => {
    jasmine.addMatchers({
        toContainText: function() {
            return {
                compare: function(actual: any, expectedText: string) {
                    var actualText = actual.textContent;
                    return {
                        pass: actualText.indexOf(expectedText) > -1,
                        get message() { return 'Expected ' + actualText + ' to contain ' + expectedText; }
                    };
                }
            };
        }
    });
});

<!DOCTYPE html>
<html>

  <head>
    <title>Iterating an Object like Array</title>

    <!-- 1. Load libraries -->
    <script src="https://code.angularjs.org/2.0.0-beta.0/angular2-polyfills.js"></script>
    <script src="https://code.angularjs.org/tools/system.js"></script>
    <script src="https://code.angularjs.org/tools/typescript.js"></script>
    <script src="https://code.angularjs.org/2.0.0-beta.0/Rx.js"></script>
    <script src="https://code.angularjs.org/2.0.0-beta.0/angular2.dev.js"></script>

    <!-- 2. Configure SystemJS -->
    <script>
      System.config({
        transpiler: 'typescript', 
        typescriptOptions: { emitDecoratorMetadata: true }, 
        packages: {'app': {defaultExtension: 'ts'}} 
      });
      System.import('app/boot')
            .then(null, console.error.bind(console));
    </script>

  </head>

  <!-- 3. Display the application -->
  <body>
    <my-app>Loading...</my-app>
  </body>

</html>

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