electron/docs/api/message-channel-main.md

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# MessageChannelMain
`MessageChannelMain` is the main-process-side equivalent of the DOM
[`MessageChannel`][] object. Its singular function is to create a pair of
connected [`MessagePortMain`](message-port-main.md) objects.
See the [Channel Messaging API][] documentation for more information on using
channel messaging.
## Class: MessageChannelMain
> Channel interface for channel messaging in the main process.
Process: [Main](../glossary.md#main-process)
Example:
```js
// Main process
const { BrowserWindow, MessageChannelMain } = require('electron')
const w = new BrowserWindow()
const { port1, port2 } = new MessageChannelMain()
w.webContents.postMessage('port', null, [port2])
port1.postMessage({ some: 'message' })
// Renderer process
const { ipcRenderer } = require('electron')
ipcRenderer.on('port', (e) => {
// e.ports is a list of ports sent along with this message
e.ports[0].onmessage = (messageEvent) => {
console.log(messageEvent.data)
}
})
```
### Instance Properties
#### `channel.port1`
A [`MessagePortMain`](message-port-main.md) property.
#### `channel.port2`
A [`MessagePortMain`](message-port-main.md) property.
[`MessageChannel`]: https://developer.mozilla.org/en-US/docs/Web/API/MessageChannel
[Channel Messaging API]: https://developer.mozilla.org/en-US/docs/Web/API/Channel_Messaging_API