umitt
About
An upgraded version of Events in Node.js core API for the browser. We only get features that we think you really need, not the whole.
Usage
Installation
$ npm install umitt // or yarn$ yarn add umitt
CDN
// unpkg // jsdelivr
Note use CDN in browser, you can call umitt
from Window API. it is available at window.umitt
Example
const emitter = // add event listeneremitter // emit eventemitter
Documents
Events: emitter
The Events class is defined and exposed by the events module:
const emitter =
All EventEmitters emit the event 'newListener'
when new listeners are added and 'removeListener'
when existing listeners are removed.
addListener(eventName, listener)
Alias for on(eventName, listener)
.
emitter
emit(eventName[, ...args])
Synchronously calls each of the listeners registered for the event named eventName
, in the order they were registered, passing the supplied arguments to each.
// without argumentemitter // with argumentemitter
eventNames()
Returns an array listing the events for which the emitter has registered listeners.
emitter
Example
const callback = {} emitter console // prints: [ 'eventName' ]
listeners(eventName)
Returns a copy of the array of listeners for the event named eventName
.
emitter
Example
const callback = {} emitter console // prints: [ [Function] ]
off(eventName, listener)
Alias for removeListener(eventName, listener)
.
on(eventName, listener)
Adds the listener function to the end of the listeners array for the event named eventName
. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventName
and listener will result in the listener being added, and called, multiple times.
// without argumentemitter; // with argumentemitter;
Example
emitteremitter // prints:// my name is Hieu Lam
once(eventName, listener)
Adds a one-time listener function for the event named eventName
. The next time eventName
is triggered, this listener is removed and then invoked.
// without argumentemitter; // with argumentemitter;
Example
emitteremitteremitter // prints:// my name is Hieu Lam
removeAllListeners([eventName])
Removes all listeners, or those of the specified eventName
.
emitter
removeListener(eventName, listener)
Removes the specified listener from the listener array for the event named eventName
.
removeListener()
will remove, at most, one instance of a listener from the listener array. If any single listener has been added multiple times to the listener array for the specified eventName
, then removeListener()
must be called multiple times to remove each instance.
emitter
Example
const callback = { console}emitteremitter// prints: my name is Hieu Lam emitteremitter// nothing
disable(eventName)
Disable the specified listeners for the event named eventName
. When listeners was disabled, it's still existed but not run when emit
called. To enbale listeners for the event, just use enable(eventName)
.
emitter
Example
const callback = { console}emitteremitter// prints: my name is Hieu Lam emitteremitter// nothing emitteremitter// prints: my name is Hieu Lam
enable(eventName)
Enable the specified listeners for the event named eventName
.
emitter
Example
const callback = { console}emitteremitter// prints: my name is Hieu Lam emitteremitter// nothing emitteremitter// prints: my name is Hieu Lam