> Portal Navigation:
> 
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> - Pages are either content pages (article or reference text) or menu pages (a list of links to child pages).
> - To get a menu page, truncate any URL to a parent path and append `.md` (e.g. `https://dev.wix.com/docs/sdk.md`, `https://dev.wix.com/docs/sdk/core-modules.md`).
> - Top-level index of all portals: https://dev.wix.com/docs/llms.txt
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# Method name: onCartChange(handler: onCartChangeHandler)

# Method package: wixEcomFrontend

# Method menu location: wixEcomFrontend --> onCartChange

# Method Link: https://dev.wix.com/docs/velo/apis/wix-ecom-frontend/on-cart-change.md

# Method Description:

Triggered when a cart changes.

Triggered when:
+ A cart is modified by native UI elements such as the 'Add to Cart' button, increase (+) and decrease (-) item quantity buttons, remove line item button (x), etc.
+ The `refreshCart()` method is called.

> **Note:** Actions performed by any method other than `refreshCart()` don't trigger `onCartChange()`.



# Method Code Examples:

*** Note: do not assume any prop names or enum values other than the ones in the example.

## Add an event handler for cart changes

```javascript
import wixEcomFrontend from 'wix-ecom-frontend';
import wixEcomBackend from 'wix-ecom-backend';

$w.onReady(function () {

  // handler function that gets the current cart on cart change
  const handler = () => {
      // The wixEcomBackend.currentCart module is universal.
      // You can call its methods in frontend and backend code.
    wixEcomBackend.currentCart.getCurrentCart()
      .then(cart => {
        let cartId = cart._id;
        console.log('cart ID: ', cartId);
      })
      .catch(error => {
        console.error(error);
        // Handle the error
      });
  };

  wixEcomFrontend.onCartChange(handler);
});
```

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