Javascript:事件多播的兼容方式实现方法

function addEventHandler(oTarget, sEventType, fnHandler)

{
if (oTarget.addEventListener)

{
oTarget.addEventListener(sEventType, fnHandler, false);
} else if (oTarget.attachEvent) {
oTarget.attachEvent("on" + sEventType, fnHandler);
} else {
oTarget["on" + sEventType] = fnHandler;
}
}