事件对象 获得 使用 冒泡 返回值

function getEvent() {
return window.event || arguments.callee.caller.arguments[0];
}
var myEvent = getEvent();
var x=y=menuOffsetWidth=menuOffsetHeight=0;
var redge=document.body.clientWidth-myEvent.clientX;
var bedge=document.body.clientHeight-myEvent.clientY;
var objRightMenu = document.getElementById("rightMenuContainer");
menuOffsetWidth = objRightMenu.offsetWidth;
menuOffsetHeight = objRightMenu.offsetHeight;
if(menuOffsetWidth == 0) menuOffsetWidth=200;
if(menuOffsetHeight == 0) menuOffsetHeight=200;
if (redge<menuOffsetWidth){
x=document.body.scrollLeft + myEvent.clientX-menuOffsetWidth;
} else {
x=document.body.scrollLeft + myEvent.clientX;
}
if (bedge<menuOffsetHeight){
y=document.body.scrollTop + myEvent.clientY - menuOffsetHeight;
} else {
y = document.body.scrollTop + myEvent.clientY;
}

myEvent.returnValue = false;
myEvent.cancelBubble=true;