CFLib.org – Common Function Library Project

Description:
Returns a lightweight object (just a struct) containing on() / off() / trigger() functions to facilitate event-driven coding in CFML

Return Values:
A struct containing functions on(), off() and trigger()

Example:

event = createEventObject();

event.on("TestEvent", function(){writeOutput("Hello World<br>");});
event.trigger("TestEvent");

Parameters:

No arguments.

Full UDF Source:

/**
 * Creates functions for event-handling in CFML
 * v1.0 by Adam Cameron
 * 
 * @return A struct containing functions on(), off() and trigger() 
 * @author Adam Cameron (dac.cfml@gmail.com) 
 * @version 1.0, December 5, 2013 
 */
function createEventObject(){
    var eventContainer = {};
    return {
        on = function(required string event, required function handler, struct data={}){
            if (!structKeyExists(eventContainer, event)){
                eventContainer[event] = [];
            }
            arrayAppend(eventContainer[event], arguments);
        },
        trigger = function(required string event, struct additionalParameters={}){
            if (structKeyExists(eventContainer, event)){
                for (eventEntry in eventContainer[event]){
                    var eventObj = {
                        event = event,
                        data = eventEntry.data
                    };
                    eventEntry.handler(event=eventObj, argumentCollection=additionalParameters);
                }
            }
        },
        off = function(required string event){
            structDelete(eventContainer, event);
        }
    };
}