Benutzerdefinierte Ereignisse-Modell ohne mithilfe von DOM-Ereignisse in JavaScript

Wenn Sie wollen ein komplett stand-alone-event-system, ohne sich auf DOM-events können Sie etwas haben, wie das mit Reaktor-Muster

function Event(name){
  this.name = name;
  this.callbacks = [];
}
Event.prototype.registerCallback = function(callback){
  this.callbacks.push(callback);
}

function Reactor(){
  this.events = {};
}

Reactor.prototype.registerEvent = function(eventName){
  var event = new Event(eventName);
  this.events[eventName] = event;
};

Reactor.prototype.dispatchEvent = function(eventName, eventArgs){
  this.events[eventName].callbacks.forEach(function(callback){
    callback(eventArgs);
  });
};

Reactor.prototype.addEventListener = function(eventName, callback){
  this.events[eventName].registerCallback(callback);
};

Verwenden Sie es wie DOM-events-Modell

var reactor = new Reactor();

reactor.registerEvent('big bang');

reactor.addEventListener('big bang', function(){
  console.log('This is big bang listener yo!');
});

reactor.addEventListener('big bang', function(){
  console.log('This is another big bang listener yo!');
});

reactor.dispatchEvent('big bang');

Live auf JSBin

Necroposting ein wenig hier, aber ich schrieb so etwas wie dieser letzten Nacht - super-einfach, und aus der Basis von Backbone.js Veranstaltungen Modul:

EventDispatcher = {

    events: {},

    on: function(event, callback) {
        var handlers = this.events[event] || [];
        handlers.push(callback);
        this.events[event] = handlers;
    },

    trigger: function(event, data) {
        var handlers = this.events[event];

        if (!handlers || handlers.length < 1)
            return;

        [].forEach.call(handlers, function(handler){
            handler(data);
        });
    }
};

Dieser Ansatz ist verblüffend einfach und erweiterbar, so dass Sie bauen eine komplexere Veranstaltung, das system auf Sie, wenn Sie brauchen.

Mithilfe der EventDispatcher ist so einfach wie:

function initializeListeners() {
    EventDispatcher.on('fire', fire); //fire.bind(this) -- if necessary
}

function fire(x) {
    console.log(x);
}

function thingHappened(thing) {
    EventDispatcher.trigger('fire', thing);
}

Mit einigen einfachen Verwendung von Namensräumen, Sie werden in der Lage sein, um pass basic-Ereignisse zwischen den Modulen mit Leichtigkeit!

Wahrscheinlich, benötigen Sie einen event-Mechanismus als ein Mittel der Kommunikation unter mehreren Objekten.

Heres, wie können Sie erreichen, dass:

JS:

/**
 * EventfulObject constructor/base.
 * @type EventfulObject_L7.EventfulObjectConstructor|Function
 */
var EventfulObject = function() {
  /**
   * Map from event name to a list of subscribers.
   * @type Object
   */
  var event = {};
  /**
   * List of all instances of the EventfulObject type.
   * @type Array
   */
  var instances = [];
  /**
   * @returns {EventfulObject_L1.EventfulObjectConstructor} An `EventfulObject`.
   */
  var EventfulObjectConstructor = function() {
    instances.push(this);
  };
  EventfulObjectConstructor.prototype = {
    /**
     * Broadcasts an event of the given name.
     * All instances that wish to receive a broadcast must implement the `receiveBroadcast` method, the event that is being broadcast will be passed to the implementation.
     * @param {String} name Event name.
     * @returns {undefined}
     */
    broadcast: function(name) {
      instances.forEach(function(instance) {
        (instance.hasOwnProperty("receiveBroadcast") && typeof instance["receiveBroadcast"] === "function") &&
        instance["receiveBroadcast"](name);
      });
    },
    /**
     * Emits an event of the given name only to instances that are subscribed to it.
     * @param {String} name Event name.
     * @returns {undefined}
     */
    emit: function(name) {
      event.hasOwnProperty(name) && event[name].forEach(function(subscription) {
        subscription.process.call(subscription.context);
      });
    },
    /**
     * Registers the given action as a listener to the named event.
     * This method will first create an event identified by the given name if one does not exist already.
     * @param {String} name Event name.
     * @param {Function} action Listener.
     * @returns {Function} A deregistration function for this listener.
     */
    on: function(name, action) {
      event.hasOwnProperty(name) || (event[name] = []);
      event[name].push({
        context: this,
        process: action
      });

      var subscriptionIndex = event[name].length - 1;

      return function() {
        event[name].splice(subscriptionIndex, 1);
      };
    }
  };

  return EventfulObjectConstructor;
}();

var Model = function(id) {
  EventfulObject.call(this);
  this.id = id;
  this.receiveBroadcast = function(name) {
    console.log("I smell another " + name + "; and I'm model " + this.id);
  };
};
Model.prototype = Object.create(EventfulObject.prototype);
Model.prototype.constructor = Model;

//---------- TEST AND USAGE (hopefully it's clear enough...)
//---------- note: I'm not testing event deregistration.

var ob1 = new EventfulObject();
ob1.on("crap", function() {
  console.log("Speaking about craps on a broadcast? - Count me out!");
});

var model1 = new Model(1);

var model2 = new Model(2);
model2.on("bust", function() {
  console.log("I'm model2 and I'm busting!");
});

var ob2 = new EventfulObject();
ob2.on("bust", function() {
  console.log("I'm ob2 - busted!!!");
});
ob2.receiveBroadcast = function() {
  console.log("If it zips, I'll catch it. - That's me ob2.");
};

console.log("start:BROADCAST\n---------------");
model1.broadcast("crap");
console.log("end  :BROADCAST\n---------------\n-\n-\n");
console.log("start:EMIT\n---------------");
ob1.emit("bust");
console.log("end:EMIT\n---------------");

HTML:

<h1>...THE SHOW IS ON YOUR CONSOLE!</h1>