> For the complete documentation index, see [llms.txt](https://docs.uibakery.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.uibakery.io/how-tos/custom-code/communicating-through-the-iframe-component.md).
# Communicating with external sites via Iframe
Let's say you have a website or application embedded in the UI Bakery Iframe component and you need to communicate with it - send or receive data. You can easily do this using the *JavaScript* `postMessage` *function*.
Follow the instruction below for details:
1. Give your Iframe component a *unique name* to send the data. \
This name will be added as a component class allowing you to query it with JavaScript.
2. Create a **JavaScript Code** action and specify the following code to query the Iframe and send messages to it:
```javascript
const iframe = document.querySelector('.uniqueName > iframe').contentWindow;
iframe.postMessage('message', { foo: 'bar' })
```
{% hint style="info" %}
Depending on the receiving app configuration, `postMessage` may require [additional setup](https://developer.mozilla.org/en-US/docs/Web/API/Window/postMessage#security_concerns).
{% endhint %}
***
Similarly, you can also *subscribe to events from the Iframe* via a **JavaScript Code** action step with the following code:
```javascript
const iframe = document.querySelector('.uniqueName > iframe').contentWindow;
iframe.on('message', (data) => {
console.log(data);
});
```
And you need to assign this action to the *On Page Load* trigger to bind the listener to the new messages when the app loads.
---
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