> Portal Navigation:
> 
> - Append `.md` to any URL under `https://dev.wix.com/docs/` to get its markdown version.
> - 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
> - Full concatenated docs: https://dev.wix.com/docs/llms-full.txt

# Method name:

siteWindow.postMessage(message: object, target: string)

# Method Link:

https://dev.wix.com/docs/sdk/frontend-modules/window/post-message.md

# Method Description:

Sends a message to a page's parent.

If a page is embedded within another site, using an [HtmlComponent](https://dev.wix.com/docs/velo/api-reference/$w/html-component/introduction.md)
 on a Wix site or an [iframe](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe)
 on a non-Wix site, call this method to send a
 message from the inner site to the outer site.

 When the parent site is a Wix site, call [`onMessage()`](https://dev.wix.com/docs/velo/api-reference/$w/html-component/on-message.md)
 to receive the message on the parent page.

 When the parent site is a non-Wix site, use the page's `window.onMessage`
 event to read the `data` property of the received `MessageEvent`
 to receive the message on the parent page.

# Method Permissions:



# Method Permissions Scopes IDs:

undefined



# Method Code Examples:

## Send a message to a Wix parent site

```javascript
/* * * * * * * * * * * * * * * * * * * * * * *
 * Code for the inner site to post a message *
 * * * * * * * * * * * * * * * * * * * * * * */
import { window } from '@wix/site-window';

// ...

await window.postMessage(dataObj);

/* * * * * * * * * * * * * * * * * * * * * * * * *
 * Code for the outer site to receive a message  *
 * * * * * * * * * * * * * * * * * * * * * * * * *
 *
 * $w("#myHtmlComponent").onMessage( (event, $x) => {
 *   let message = event.data;
 * } );
 */
```

## Send a message to a non-Wix parent site

```javascript
/* * * * * * * * * * * * * * * * * * * * * * *
 * Code for the inner site to post a message *
 * * * * * * * * * * * * * * * * * * * * * * */
import { window } from '@wix/site-window';

// ...

await window.postMessage(dataObj);

/* * * * * * * * * * * * * * * * * * * * * * * * *
 * Code for the outer site to receive a message  *
 * * * * * * * * * * * * * * * * * * * * * * * * *
 *
 * <script>
 *   window.addEventListener("message", event => {
 *    let message = event.data;
 *   } );
 * </script>
 */
```