Modul Acara Node.js
Contoh
Jadikan event listener untuk event yang disebut "scream", lalu provokasi event tersebut:
var events = require('events');
var eventEmitter = new
events.EventEmitter();
eventEmitter.on('scream', function() {
console.log('A scream is detected!');
});
eventEmitter.emit('scream');
Definisi dan Penggunaan
Modul Acara menyediakan cara bekerja dengan acara.
Di Node.js, semua peristiwa adalah turunan dari objek EventEmitter
Sintaksis
Sintaks untuk menyertakan modul Events, dan membuat EventEmitter di aplikasi Anda:
var events = require('events');
var eventEmitter = new events.EventEmitter();
Properti dan Metode EventEmitter
Method | Description |
---|---|
addListener() | Adds the specified listener |
defaultMaxListeners | Sets the maximum number of listeners allowed for one event. Default is 10 |
emit() | Call all the listeners registered with the specified name |
eventNames() | Returns an array containing all registered events |
getMaxListeners() | Returns the maximum number of listeners allowed for one event |
listenerCount() | Returns the number of listeners with the specified name |
listeners() | Returns an array of listeners with the specified name |
on() | Adds the specified listener |
once() | Adds the specified listener once. When the specified listener has been executed, the listener is removed |
prependListener() | Adds the specified listener as the first event with the specified name |
prependOnceListener() | Adds the specified listener as the first event with the specified name, once. When the specified listener has been executed, the listener is removed |
removeAllListeners() | Removes all listeners with the specified name, or ALL listeners if no name is specified |
removeListener() | Removes the specified listener with the specified name |
setMaxListeners() | Sets the maximum number of listeners allowed for one event. Default is 10 |