스크롤 막대가 페이지의 끝에 도달했는지 판단하기

  
    

   
     //
   
       
   
     

   
     function
   
      getScrollTop() 
{ 
 
   
     var
   
      scrollTop
   
     =
   
     0
   
     ; 
 
   
     if
   
     (document.documentElement
   
     &&
   
     document.documentElement.scrollTop) 
 { 
 scrollTop
   
     =
   
     document.documentElement.scrollTop; 
 } 
 
   
     else
   
      
   
     if
   
     (document.body) 
 { 
 scrollTop
   
     =
   
     document.body.scrollTop; 
 } 
 
   
     return
   
      scrollTop; 
} 
 
 
 
   
     //
   
       
   
     

   
     function
   
      getClientHeight() 
{ 
 
   
     var
   
      clientHeight
   
     =
   
     0
   
     ; 
 
   
     if
   
     (document.body.clientHeight
   
     &&
   
     document.documentElement.clientHeight) 
 { 
 
   
     var
   
      clientHeight 
   
     =
   
      (document.body.clientHeight
   
     <
   
     document.documentElement.clientHeight)
   
     ?
   
     document.body.clientHeight:document.documentElement.clientHeight; 
 } 
 
   
     else
   
      
 { 
 
   
     var
   
      clientHeight 
   
     =
   
      (document.body.clientHeight
   
     >
   
     document.documentElement.clientHeight)
   
     ?
   
     document.body.clientHeight:document.documentElement.clientHeight; 
 } 
 
   
     return
   
      clientHeight; 
} 
 
 
 
   
     //
   
       
   
     

   
     function
   
      getScrollHeight() 
{ 
 
   
     return
   
      Math.max(document.body.scrollHeight,document.documentElement.scrollHeight); 
} 
 
   
     function
   
      test(){ 
 
   
     if
   
      (getScrollTop()
   
     +
   
     getClientHeight()
   
     ==
   
     getScrollHeight()){ 
 alert(
   
     "
   
      
   
     "
   
     ); 
 }
   
     else
   
     { 
 alert(
   
     "
   
      
   
     "
   
     ); 
 } 
 }