function getPageSize() 
...{
var xScroll, yScroll; if (window.innerHeight && window.scrollMaxY)
...{ xScroll = document.body.scrollWidth; yScroll = window.innerHeight + window.scrollMaxY;
} else if (document.body.scrollHeight > document.body.offsetHeight) ...{ xScroll = document.body.scrollWidth; yScroll = document.body.scrollHeight; } else ...{ xScroll = document.body.offsetWidth; yScroll = document.body.offsetHeight; } var windowWidth, windowHeight; if (self.innerHeight) ...{ windowWidth = self.innerWidth; windowHeight = self.innerHeight; } else if (document.documentElement && document.documentElement.clientHeight) ...{ windowWidth = document.documentElement.clientWidth; windowHeight = document.documentElement.clientHeight; } else if (document.body) ...{ windowWidth = document.body.clientWidth; windowHeight = document.body.clientHeight; } if (yScroll < windowHeight) ...{ pageHeight = windowHeight; } else ...{ pageHeight = yScroll; } if (xScroll < windowWidth) ...{ pageWidth = windowWidth; } else ...{ pageWidth = xScroll; } arrayPageSize = new Array(pageWidth, pageHeight, windowWidth, windowHeight); return arrayPageSize;
} getScrollTop函数获得当前页面的滚动条纵坐标位置。在给页面添加了
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
后，document.body.scrollTop永远等于0。此时可以用这个方法来获得scrollTop。
function getScrollTop()...{ if (typeof window.pageYOffset != 'undefined') ...{ return window.pageYOffset; } else if (typeof document.compatMode != 'undefined' && document.compatMode != 'BackCompat') ...{ return document.documentElement.scrollTop; } else if (typeof document.body != 'undefined') ...{ return document.body.scrollTop; } }