Communicate asynchronously from a renderer process to the main process.
Process: Renderer
The ipcRenderer
module is an instance of the EventEmitter class. It 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.
The ipcRenderer
module has the following method to listen for events and send messages:
ipcRenderer.on(channel, listener)
channel
Stringlistener
FunctionListens to channel
, when a new message arrives listener
would be called with listener(event, args...)
.
ipcRenderer.once(channel, listener)
channel
Stringlistener
FunctionAdds a one time listener
function for the event. This listener
is invoked only the next time a message is sent to channel
, after which it is removed.
ipcRenderer.removeListener(channel, listener)
channel
Stringlistener
FunctionRemoves the specified listener
from the listener array for the specified channel
.
ipcRenderer.removeAllListeners([channel])
channel
String (optional)Removes all listeners, or those of the specified channel
.
ipcRenderer.send(channel[, arg1][, arg2][, ...])
channel
String...args
any[]Send a message to the main process asynchronously via channel
, you can also send arbitrary arguments. Arguments will be serialized in JSON internally and hence no functions or prototype chain will be included.
The main process handles it by listening for channel
with ipcMain
module.
ipcRenderer.sendSync(channel[, arg1][, arg2][, ...])
channel
String...args
any[]Returns any
- The value sent back by the ipcMain
handler.
Send a message to the main process synchronously via channel
, you can also send arbitrary arguments. Arguments will be serialized in JSON internally and hence no functions or prototype chain will be included.
The main process handles it by listening for channel
with ipcMain
module, and replies by setting 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...args
any[]Like ipcRenderer.send
but the event will be sent to the <webview>
element in the host page instead of the main process.