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){ // all but Explorer Mac 
      xScroll = document.body.scrollWidth; 
      yScroll = document.body.scrollHeight; 
   } else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari 
      xScroll = document.body.offsetWidth; 
      yScroll = document.body.offsetHeight; 
   } 
    	
   var windowWidth, windowHeight; 
   if (self.innerHeight) {   // all except Explorer 
      windowWidth = self.innerWidth; 
      windowHeight = self.innerHeight; 
   } else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode 
      windowWidth = document.documentElement.clientWidth; 
      windowHeight = document.documentElement.clientHeight; 
   } else if (document.body) { // other Explorers 
      windowWidth = document.body.clientWidth; 
      windowHeight = document.body.clientHeight; 
   }    
    
   // for small pages with total height less then height of the viewport 
   if(yScroll < windowHeight){ 
      pageHeight = windowHeight; 
   } else { 
      pageHeight = yScroll; 
   } 

   // for small pages with total width less then width of the viewport 
   if(xScroll < windowWidth){    
      pageWidth = windowWidth; 
   } else { 
      pageWidth = xScroll; 
   } 	 
   arrayPageSize = new Array(pageWidth,pageHeight,windowWidth,windowHeight) 
   return arrayPageSize; 
}