title: How to push in array?
body: <p>I'm trying to do cart by angular2(TS)</p>
  
  <pre><code>import {Injectable} from 'angular2/core';    
  import {Cart} from './product'; //interface id: Number; name: String
  
   @Injectable()
   export class ProductService {
   public products;
   public cart : Cart[] = [];
  
      addToCart(products: Object) {
        console.log('product=',products)
        this.cart.push(this.products);
        console.log('cart=',this.cart);
             }
  </code></pre>
  
  <p>When I push products in method I get </p>
  
  <pre><code>product= Object {id: 13, name: "Bombasto"}
  </code></pre>
  
  <p>but in </p>
  
  <pre><code>console.log('cart=',this.cart);
  </code></pre>
  
  <p>I have "undefined". Why?</p>