请问如何通过键盘的上下键控制表格行的高亮显示？

Question

<style>
tr.highlight{
background:#08246B;
color:white;
}
</style>
<table border="1" width="70%" id="ice">
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
</table><script language="javascript">
<!--
var currentLine = -1;
document.onkeydown = function () 
{
//alert(event.keyCode);
switch (event.keyCode) 
{
case 38:
   currentLine--;
               changeItem();
               break;
case 40:
   currentLine++;
               changeItem();
               break;
            default :
               break;
}
}//改变选择项目
function changeItem()
{
var it = document.getElementById("ice").children[0];
for (i=0;i<it.rows.length;i++) 
{
it.rows[i].className = "";
}
if (currentLine < 0)
currentLine = it.rows.length - 1;
if (currentLine == it.rows.length)
currentLine = 0;
it.rows[currentLine].className = "highlight";
}//-->
</script>

Answer 1

兼容一下firefox<style>
tr.highlight{
background:#08246B;
color:white;
}
</style>
<table border="1" width="70%" id="ice">
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
</table><script language="javascript">
<!--
var currentLine = -1;
document.onkeydown = function (e) 
{
e = window.event || e;
switch (e.keyCode) 
{
case 38:
   currentLine--;
               changeItem();
               break;
case 40:
   currentLine++;
               changeItem();
               break;
            default :
               break;
}
}//改变选择项目
function changeItem()
{
if( document.all )
var it = document.getElementById("ice").children[0];
else
var it = document.getElementById("ice"); for (i=0;i<it.rows.length;i++) 
{
it.rows[i].className = "";
}
if (currentLine < 0)
currentLine = it.rows.length - 1;
if (currentLine == it.rows.length)
currentLine = 0;
it.rows[currentLine].className = "highlight";
}//-->
</script>