> ## Documentation Index
> Fetch the complete documentation index at: https://docs.wearepion.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Promo Code Event

When a user issues a promo code through an embedded landing page our `<script>` will fire a custom event for you to hook into. This can be utilized to automatically apply the code for the user in checkout.

To utilize this event you can use the following in your JavaScript code:

```
window.addEventListener('sbCodeCallback', (callbackData) => {
  const { code } = callbackData.detail

  // You can do whatever you need to do with the `code`
})
```

`callbackData` is an object with the following properties:

```
{
  detail: {
    code: 'example_code'
  }
}
```