electron/docs/api/ipc-renderer.md

ipcRenderer

The ipcRenderer module provides a few methods so you can send synchronous and asynchronous messages from the render process (web page) to the main process. You can also receive replies from the main process.

See ipcMain for code examples.

Listening for Messages

The ipcRenderer module has the following method to listen for events:

ipcRenderer.on(channel, callback)

• channel String - The event name.
• callback Function

When the event occurs the callback is called with an event object and arbitrary arguments.

Sending Messages

The ipcRenderer module has the following methods for sending messages:

ipcRenderer.send(channel[, arg1][, arg2][, ...])

• channel String - The event name.
• arg (optional)

Send an event to the main process asynchronously via a channel, you can also send arbitrary arguments. The main process handles it by listening for the channel event with ipcMain.

ipcRenderer.sendSync(channel[, arg1][, arg2][, ...])

• channel String - The event name.
• arg (optional)

Send an event to the main process synchronously via a channel, you can also send arbitrary arguments. The main process handles it by listening for the channel event with ipcMain.

The main process handles it by listening for the channel event with ipc and replies by setting the event.returnValue.

Note: Sending a synchronous message will block the whole renderer process, unless you know what you are doing you should never use it.

ipcRenderer.sendToHost(channel[, arg1][, arg2][, ...])

• channel String - The event name.
• arg (optional)

Like ipcRenderer.send but the event will be sent to the <webview> element in the host page instead of the main process.