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doc refactor: events

v0.9.1-release
isaacs 13 years ago
parent
commit
ec02e82760
  1. 25
      doc/api/events.markdown

25
doc/api/events.markdown

@ -1,4 +1,4 @@
## Events
# Events
Many objects in Node emit events: a `net.Server` emits an event each time
a peer connects to it, a `fs.readStream` emits an event when the file is
@ -12,7 +12,7 @@ Functions can then be attached to objects, to be executed when an event
is emitted. These functions are called _listeners_.
### events.EventEmitter
## Class: events.EventEmitter
To access the EventEmitter class, `require('events').EventEmitter`.
@ -24,8 +24,8 @@ trace and exit the program.
All EventEmitters emit the event `'newListener'` when new listeners are
added.
#### emitter.addListener(event, listener)
#### emitter.on(event, listener)
### emitter.addListener(event, listener)
### emitter.on(event, listener)
Adds a listener to the end of the listeners array for the specified event.
@ -33,7 +33,7 @@ Adds a listener to the end of the listeners array for the specified event.
console.log('someone connected!');
});
#### emitter.once(event, listener)
### emitter.once(event, listener)
Adds a **one time** listener for the event. This listener is
invoked only the next time the event is fired, after which
@ -43,7 +43,7 @@ it is removed.
console.log('Ah, we have our first user!');
});
#### emitter.removeListener(event, listener)
### emitter.removeListener(event, listener)
Remove a listener from the listener array for the specified event.
**Caution**: changes array indices in the listener array behind the listener.
@ -56,12 +56,12 @@ Remove a listener from the listener array for the specified event.
server.removeListener('connection', callback);
#### emitter.removeAllListeners([event])
### emitter.removeAllListeners([event])
Removes all listeners, or those of the specified event.
#### emitter.setMaxListeners(n)
### emitter.setMaxListeners(n)
By default EventEmitters will print a warning if more than 10 listeners are
added for a particular event. This is a useful default which helps finding memory leaks.
@ -69,7 +69,7 @@ Obviously not all Emitters should be limited to 10. This function allows
that to be increased. Set to zero for unlimited.
#### emitter.listeners(event)
### emitter.listeners(event)
Returns an array of listeners for the specified event. This array can be
manipulated, e.g. to remove listeners.
@ -79,12 +79,13 @@ manipulated, e.g. to remove listeners.
});
console.log(util.inspect(server.listeners('connection'))); // [ [Function] ]
#### emitter.emit(event, [arg1], [arg2], [...])
### emitter.emit(event, [arg1], [arg2], [...])
Execute each of the listeners in order with the supplied arguments.
#### Event: 'newListener'
### Event: 'newListener'
`function (event, listener) { }`
* `event` {String} The event name
* `listener` {Function} The event handler function
This event is emitted any time someone adds a new listener.

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