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Getting the event object

oEvent.eventPhase = 2;

oEvent.isChar = (oEvent.charCode > 0);

oEvent.pageX = oEvent.clientX + document.body.scrollLeft;

oEvent.pageY = oEvent.clientY + document.body.scrollTop;

oEvent.preventDefault = function () {

this.returnValue = false;

};

if (oEvent.type == “mouseout”) {

oEvent.relatedTarget = oEvent.toElement;

} else if (oEvent.type == “mouseover”) {

oEvent.relatedTarget = oEvent.fromElement;

}

oEvent.stopPropagation = function () {

this.cancelBubble = true;

};

oEvent.target = oEvent.srcElement;

oEvent.time = (new Date).getTime();

}

return oEvent;

};

Because the

type

property is the same in both IE and the DOM, this is the end of the method. However,

this method isn’t intended to be used alone. Instead, it is intended to be used inside of another method

that gets a reference to the

event

object.

Getting the event object

Unfortunately, IE and the DOM use very different methods to get the

event

object. In IE, the

event

object is tied to the

window

object although in the DOM it is independent of any other object and is

passed in as an argument. Because of this, it is very difficult to make IE’s event model act like Mozilla’s,

or vice versa. Instead of trying to make one like the other, you can create a new method that can be used

by both browsers called

getEvent()

The

getEvent()

method accepts no arguments and its sole purpose is to return the event object. The

first case it deals with is IE, checking for the existence of

window.event

and then using

formatEvent()

before returning the

event

object:

EventUtil.getEvent = function() {

if (window.event) {

return this.formatEvent(window.event);

}

};

Next up is the DOM case. Remember, DOM-compliant browsers pass the

event

object as an argument

to the event handler. This is when it pays to remember that a function is actually an object that has prop-

erties. In this case, the property of interest is called

caller

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All about Events

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