/*
  Author : 最后一秒.bat
  para :
    obj             ----   div对象
    site            ----   位置标识(整数)
    LeftMargin      ----   左部填充
    RightMargin     ----   右部填充
    TopMargin       ----   顶部填充
    BottomMargin    ----   底部填充
*/
function DivMain(id, site, LeftMargin, RightMargin, TopMargin, BottomMargin )
{
  if(LeftMargin == undefined)
    LeftMargin = 0;
  if(RightMargin == undefined)
    RightMargin = 0;
  if(TopMargin == undefined)
    TopMargin = 0;
  if(BottomMargin == undefined)
    BottomMargin = 0;

  var obj = document.getElementById(id);
  //左端横坐标，中部横坐标，右端横坐标
  var xLeft, xCenter, xRigth;
  //上端纵坐标，中部纵坐标，下端纵坐标
  var yTop, yMiddle, yBottom;

  xLeft   = (document.documentElement.scrollLeft) + LeftMargin +"px";
  xCenter = (document.documentElement.scrollLeft + (document.documentElement.clientWidth-obj.offsetWidth)/2) + LeftMargin + RightMargin + "px";
  xRigth  = (document.documentElement.scrollLeft + document.documentElement.clientWidth-obj.offsetWidth) + RightMargin + "px";
  yTop    = (document.documentElement.scrollTop) + TopMargin + "px";
  yMiddle = (document.documentElement.scrollTop + (document.documentElement.clientHeight-obj.offsetHeight)/2) + TopMargin + BottomMargin + "px";
  yBottom = (document.documentElement.scrollTop + document.documentElement.clientHeight-obj.offsetHeight) + BottomMargin + "px";
  
  switch(site)
  {
    case 0 :         //左上
      obj.style.top  = yTop;
      obj.style.left = xLeft;
      break;
    case 1 :         //上中
      obj.style.top  = yTop;
      obj.style.left = xCenter;
      break;
    case 2 :         //右上
      obj.style.top  = yTop;
      obj.style.left = xRigth;
      break;
    case 3 :         //左中
      obj.style.top  = yMiddle;
      obj.style.left = xLeft;
      break;
    case 4 :         //正中
      obj.style.top  = yMiddle;
      obj.style.left = xCenter;
      break;
    case 5 :         //右中
      obj.style.top   = yMiddle;
      obj.style.left = xRigth;
      break;
    case 6 :         //左下
      obj.style.top   = yBottom;
      obj.style.left = xLeft;
      break;
    case 7 :         //下中
      obj.style.top   = yBottom;
      obj.style.left = xCenter;
      break;
    case 8 :         //右下
      obj.style.top   = yBottom;
      obj.style.left = xRigth;
      break;
  }
}

function DivRun()
{
  DivMain( 'LeftDiv', 3 , 10, 0, -6, 0 );
}


window.onscroll = DivRun;
window.onresize = DivRun;
window.onload   = DivRun;