动态添加数据

var arr=[
     {"key":"庄,8,3,5,8"},
     {"key":"闲,7,7,7,7"},
     {"key":"庄,6,3,8,5"},
     {"key":"闲,1,2,4,5"},
     {"key":"庄,5,5,5"},
     {"key":"闲,9,9,9"}
];

我有一组数组数据不定长度的，我想把他添加到table里要怎么添，
两个数组为一个td,
如果最到后一组td数组了，
后面要加上一个“下注在：”，
默认第一个tr显示其它两个隐藏，用jquery怎么写,
形式如下:



<table class="tablelist" width="100%" border="0" cellspacing="0" cellpadding="0">
    <tr>
     <td colspan="2">
     <font>庄</font>：<span>8</span><span>3</span><span>5</span><span>8</span>&nbsp;
     <font>闲</font>：<span>7</span><span>7</span><span>7</span><span>7</span>&nbsp;
     </td>
    </tr>
    <tr style="display:none">
     <td colspan="2">
     <font>庄</font>：<span>6</span><span>3</span><span>8</span><span>5</span>&nbsp;
     <font>闲</font>：<span>1</span><span>2</span><span>4</span><span>5</span>&nbsp;
     </td>
    </tr>
    <tr style="display:none">
     <td colspan="2">
     <font>庄</font>：<span>5</span><span>5</span><span>5</span>&nbsp;
     <font>闲</font>：<span>9</span><span>9</span><span>9</span>&nbsp;
     下注在：
     </td>
    </tr>
</table>

---

javascriptvar count = Math.floor(count(arr) / 2) - 1;
var html = '<table class="tablelist" width="100%" border="0" cellspacing="0" cellpadding="0">';
for (i in arr) {
    var mod = i % 2;
    if (mod == 0) {
        var style = mod  == 0 ? 'display:none' : '';
        var xiazhu = count == i / 2 ? '下注在：' : '';
        html += '<tr style="' + style + '">\
         <td colspan="2">\
         <!-- arr[i] -->\
         <font>庄</font>：<span>5</span><span>5</span><span>5</span>&nbsp;\
         <!-- arr[i + 1] -->\
         <font>闲</font>：<span>9</span><span>9</span><span>9</span>&nbsp;\
         ' + xiazhu + '\
         </td>\
        </tr>';
    }
 }
html += '</table>';