I don't Know

Window message:
    WM_SCROLL      276    // Horizontal scroll
    WM_VSCROLL     277    // Vertical scroll

Parameters:
    SB_LINEUP      0      // Scrolls one line up.
    SB_LINELEFT    0
    SB_LINEDOWN    1      // Scrolls one line down.
    SB_LINERIGHT   1
    SB_PAGEUP      2      // Scrolls one page up.
    SB_PAGELEFT    2
    SB_PAGEDOWN    3      // Scrolls one page down.
    SB_PAGERIGHT   3
    SB_TOP         6      // Scrolls to the upper left.
    SB_LEFT        6
    SB_BOTTOM      7      // Scrolls to the lower right.
    SB_RIGHT       7
    SB_ENDSCROLL   8      // Ends scroll.
   
[powerscript]
//
//  Scroll Window one page down
//    WM_VSCROLL  = 277
//    SB_PAGEDOWN = 3
//
Send(Handle(this), 277, 3, 0)  // 277은 Vertical scroll,  276   Horizontal scroll , 3:pagedown

[윈도우 Key이벤트에 기술]
/* 윈도우 스크롤*/
choose case  key
 case KeyHome!
  send(handle(this),277,6,0)
 case KeyEnd!
  send(handle(this),277,7,0) 
 case KeyupArrow!
   send(handle(this),277,0,0)

 case  KeyDownArrow!
  send(handle(this),277,1,0)
 case  KeyPageUp!
  send(handle(this),277,2,0)
 case  KeyPageDown!
  send(handle(this),277,3,0)
end choose