javascript事件模型框架-eventutil.js

var EventUtil = new Object;
/**//*
此方法用来给特定对象添加事件，oTarget是指定对象,sEventType是事件类型，如click、keydown等， fnHandler是事件回调函数
/*
EventUtil.addEventHandler = function (oTarget, sEventType, fnHandler) {
//firefox情况下
if (oTarget.addEventListener) {
oTarget.addEventListener(sEventType, fnHandler, false);
}
//IE下
else if (oTarget.attachEvent) {
oTarget.attachEvent("on" + sEventType, fnHandler);
}
else {
oTarget["on" + sEventType] = fnHandler;
}
};
/*
此方法用来移除特定对象的特定事件，oTarget是指定对象,sEventType是事件类型，如click、keydown等，fnHandler是事件回调函数
/*
EventUtil.removeEventHandler = function (oTarget, sEventType, fnHandler) {
if (oTarget.removeEventListener) {
oTarget.removeEventListener(sEventType, fnHandler, false);
} else if (oTarget.detachEvent) {
oTarget.detachEvent("on" + sEventType, fnHandler);
} else {
oTarget["on" + sEventType] = null;
}
};

/*
格式化事件，因为IE和其他浏览器下获取事件的方式不同并且事件的属性也不尽相同，通过此方法提供一个一致的事件
*/
EventUtil.formatEvent = function (oEvent) {
//isIE和isWin引用到一个js文件，判断浏览器和操作系统类型
if (isIE && isWin) {
oEvent.charCode = (oEvent.type == "keypress") ? oEvent.keyCode : 0;
//IE只支持冒泡，不支持捕获
oEvent.eventPhase = 2;
oEvent.isChar = (oEvent.charCode > 0);
oEvent.pageX = oEvent.clientX + document.body.scrollLeft;
oEvent.pageY = oEvent.clientY + document.body.scrollTop;
//阻止事件的默认行为
oEvent.preventDefault = function () {
this.returnValue = false;
};

//将toElement,fromElement转化为标准的relatedTarget
if (oEvent.type == "mouseout") {
oEvent.relatedTarget = oEvent.toElement;
} else if (oEvent.type == "mouseover") {
oEvent.relatedTarget = oEvent.fromElement;
}
//取消冒泡
oEvent.stopPropagation = function () {
this.cancelBubble = true;
};

oEvent.target = oEvent.srcElement;
//添加事件发生时间属性，IE没有
oEvent.time = (new Date).getTime();
}
return oEvent;
};

EventUtil.getEvent = function() {
if (window.event) {
//格式化IE的事件
return this.formatEvent(window.event);
} else {
return EventUtil.getEvent.caller.arguments[0];
}
};