请问一下，QQ游戏桌子的效果，怎样实现？（

Question

随便写个，能看到效果就行了，真用的话，要考虑到同时会有很多人连接，页面刷新的问题。<Script>
var last_table=0;
var last_seat=0;
function sit_down(table,seat)
{
    stand_up(last_table,last_seat);
var theobj=eval("document.all.seat_"+table+"_"+seat);
theobj.innerHTML="<img src='http://jump.jojohot.com/image/image/1/555/rq056.gif' width=40 height=40>";
last_table=table;
last_seat=seat;
}function stand_up(table,seat)
{
    if(table>0&&seat>0)
{
var theobj=eval("document.all.seat_"+table+"_"+seat);
    theobj.innerHTML="<input type=button name=Submit value='坐啊哥们' onclick='sit_down("+table+","+seat+")'>";    
}
}
</script>
<table width="300" border="0" cellspacing="1" cellpadding="1">
  <tr>
    <td>&nbsp;</td>
    <td height="50">
<div align="center">
        <span id="seat_1_1"><input type="button" name="Submit" value="坐啊哥们" onclick="sit_down(1,1)"></span>
      </div></td>
    <td>&nbsp;</td>
  </tr>
  <tr>
    <td width="50">
<div align="center">
        <span id="seat_1_2"><input type="button" name="Submit2" value="坐啊哥们" onclick="sit_down(1,2)"></span>
      </div></td>
    <td width="200" height="200" bgcolor="#003399">
<div align="center"><font color="#FFFFFF">I am a table 1</font></div></td>
    <td width="50">
<div align="center">
        <span id="seat_1_3"><input type="button" name="Submit2" value="坐啊哥们" onclick="sit_down(1,3)"></span>
      </div></td>
  </tr>
  <tr>
    <td>&nbsp;</td>
    <td height="50">
<div align="center">
        <span id="seat_1_4"><input type="button" name="Submit2" value="坐啊哥们" onclick="sit_down(1,4)"></span>
      </div></td>
    <td>&nbsp;</td>
  </tr>
</table>
<br>
<table width="300" border="0" cellspacing="1" cellpadding="1">
  <tr> 
    <td>&nbsp;</td>
    <td height="50"> <div align="center"> 
        <span id="seat_2_1"><input type="button" name="Submit2" value="坐啊哥们" onclick="sit_down(2,1)"></span>
      </div></td>
    <td>&nbsp;</td>
  </tr>
  <tr> 
    <td width="50"> <div align="center"> 
        <span id="seat_2_2"><input type="button" name="Submit2" value="坐啊哥们" onclick="sit_down(2,2)"></span>
      </div></td>
    <td width="200" height="200" bgcolor="#003399"> <div align="center"><font color="#FFFFFF">I 
        am a table</font></div></td>
    <td width="50"> <div align="center"> 
        <span id="seat_2_3"><input type="button" name="Submit2" value="坐啊哥们" onclick="sit_down(2,3)"></span>
      </div></td>
  </tr>
  <tr> 
    <td>&nbsp;</td>
    <td height="50"> <div align="center"> 
        <span id="seat_2_4"><input type="button" name="Submit2" value="坐啊哥们" onclick="sit_down(2,4)"></span>
      </div></td>
    <td>&nbsp;</td>
  </tr>
</table>