2.6 KiB
ipcRenderer
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.
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.
ipcRenderer.removeListener(channel, callback)
channel
String - The event name.callback
Function - The reference to the same function that you used foripcRenderer.on(channel, callback)
Once done listening for messages, if you no longer want to activate this callback and for whatever reason can't merely stop sending messages on the channel, this function will remove the callback handler for the specified channel.
ipcRenderer.removeAllListeners(channel)
channel
String - The event name.
This removes all handlers to this ipc channel.
ipcRenderer.once(channel, callback)
Use this in place of ipcRenderer.on()
to fire handlers meant to occur only once,
as in, they won't be activated after one call of callback
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. Arguments will be serialized (json) and hence no functions or prototype chain will be included. 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
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 - 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.