具体方法:

function getTotalHeight(){
             
            if($.browser.msie){
                return document.compatMode == "CSS1Compat"? document.documentElement.clientHeight :
                         document.body.clientHeight;
            }else{
                return self.innerHeight;
            }
        }

         function getTotalWidth (){
             
            if($.browser.msie){
                return document.compatMode == "CSS1Compat"? document.documentElement.clientWidth :
                         document.body.clientWidth;
            }else{
                return self.innerWidth;
            }
        }  

from: http://www.blogjava.net/alexwan/archive/2008/10/22/235827.html