Exercises from Chapter 13 of Eloquent Javascript

Chapter13.js

// Ex 13.1 of Chapter 13 in Eloquent Javascript

// Write a function called registerEventHandler to wrap the
// incompatibilities of these two models. It takes three arguments: first
// a DOM node that the handler should be attached to, then the name of
// the event type, such as "click" or "keypress", and finally the handler
// function. 

function registerEventHandler (node, eventType, handlerFN) {
 	 if (node.attachEvent) { //IE
	 node.attachEvent("on"+eventType, handlerFN);
	 else // all others
	 node.addEventListener(eventType, handlerFN, false);

}

// okay, that works. There might be other ways to check whether a method on a node exists or not
// EloquentJavascript solution: 
//function registerEventHandler(node, event, handler) {
//  if (typeof node.addEventListener == "function")
//    node.addEventListener(event, handler, false);
//  else
//    node.attachEvent("on" + event, handler);
//}