jquery获取滚动条位置：页面大小,滚动条位置,元素位置

//页面位置及窗口大小
function GetPageSize() {
var scrW, scrH;
if(window.innerHeight && window.scrollMaxY)
{    // Mozilla   
scrW = window.innerWidth + window.scrollMaxX;   
scrH = window.innerHeight + window.scrollMaxY;
}
else if(document.body.scrollHeight > document.body.offsetHeight)
{    // all but IE Mac   
scrW = document.body.scrollWidth;   
scrH = document.body.scrollHeight;
} else if(document.body)
{ // IE Mac   
scrW = document.body.offsetWidth;   
scrH = document.body.offsetHeight;
}
var winW, winH;
if(window.innerHeight)
{ // all except IE   
winW = window.innerWidth;
winH = window.innerHeight;
} else if (document.documentElement && document.documentElement.clientHeight)
{    // IE 6 Strict Mode   
winW = document.documentElement.clientWidth;    
winH = document.documentElement.clientHeight;
} else if (document.body) { // other   
winW = document.body.clientWidth;   
winH = document.body.clientHeight;
}    // for small pages with total size less then the viewport
var pageW = (scrW<winW) ? winW : scrW;
var pageH = (scrH<winH) ? winH : scrH;   
return {PageW:pageW, PageH:pageH, WinW:winW, WinH:winH};
};
//滚动条位置
function GetPageScroll()
{
var x, y; if(window.pageYOffset)
{    // all except IE   
y = window.pageYOffset;   
x = window.pageXOffset;
} else if(document.documentElement && document.documentElement.scrollTop)
{    // IE 6 Strict   
y = document.documentElement.scrollTop;   
x = document.documentElement.scrollLeft;
} else if(document.body) {    // all other IE   
y = document.body.scrollTop;   
x = document.body.scrollLeft;  
}
return {X:x, Y:y};
}