javascript高手帮忙看一个下拉列表的问题

[cpzhg]

<select name="text" onChange="test_change()">
<option value="" selected>请选择</option>
<option value="1" selected>test1</option>
<option value="2" selected>test2</option>
<option value="3" selected>test3</option>
</select>

<tr>
<td>test1</td>
</tr>

<tr>
<td>test2</td>
</tr>

如果我在下拉列表框中选择"test1"就出现第一个tr,同理我选择"test2"就出现第二个tr,网页在加载时什么都不显示,请问这个test_change()怎么写呀,请高手帮忙

[ice_berg16]

使用prototype.js库可以更方便一些

<select name="text" onChange="test_change(this)">
<option value="">请选择</option>
<option value="t1">test1</option>
<option value="t1,t2">test2</option>
<option value="t1,t2,t3">test3</option>
</select>
<table>
<tr id="t1">
<td>test1</td>
</tr>

<tr id="t2">
<td>test2</td>
</tr>
<tr id="t3">
<td>test3</td>
</tr>
</table>
<script language="javascript" src="prototype.js"></script>
<script language="javascript">
<!--
Element.hide("t1","t2","t3");
function test_change(o){
Element.hide("t1","t2","t3");
Element.show.apply(window,o.value.split(","));
}
//-->
</script>

[meizz]

prototype.js 稍微看了一下，不妥之处与错误不少

[cpzhg]

谢谢meizz(梅花雪)大哥,但现在有一个新问题,如果value值不是1,2,3而是相对应的test1,test2,test3这个js怎么写?

[meizz]

<select name="text" onChange="test_change(this)">
<option value="" selected>请选择</option>
<option value="1" selected>test1</option>
<option value="2" selected>test2</option>
<option value="3" selected>test3</option>
</select>

<table id="tab" border=1>
<tr style="display: none">
<td>test1</td>
</tr>

<tr style="display: none">
<td>test2</td>
</tr>

<tr style="display: none">
<td>test2</td>
</tr>

</table>

<SCRIPT LANGUAGE="JavaScript">
function test_change(e)
{
var tab = document.getElementById("tab");
for(var i=0; i<tab.rows.length; i++)
tab.rows[i].style.display = "none";
var s = e.selectedIndex;
if(s!=-1)
{
tab.rows[s - 1].style.display = "";
}
}
</SCRIPT>

[cpzhg]

<select name="text" onChange="test_change(this)">
<option value="" selected>请选择</option>
<option value="test1" selected>test1</option>
<option value="test2" selected>test2</option>
<option value="test3" selected>test3</option>
</select>

你没有理解我的意思,如果value的值为test1,test2,test3时js该怎么写?

[meizz]

你试试看我改过的JS代码呀！自己连测试都不测试一下

[cpzhg]

我测试过了,不行呀！

[ice_berg16]

prototype.js 稍微看了一下，不妥之处与错误不少

我看了很长时间，有些代码还没有转过弯来，你觉得哪些地方有问题？

[meizz]

<select name="text" onChange="test_change(this)">
<option value="" selected>please select</option>
<option value="test1" selected>test1</option>
<option value="test2" selected>test2</option>
<option value="test3" selected>test3</option>
</select>

<table id="tab" border=1>
<tr style="display: none">
<td>test1</td>
</tr>

<tr style="display: none">
<td>test2</td>
</tr>

<tr style="display: none">
<td>test3</td>
</tr>

</table>

<SCRIPT LANGUAGE="JavaScript">
function test_change(e)
{
var tab = document.getElementById("tab");
for(var i=0; i<tab.rows.length; i++)
tab.rows[i].style.display = "none";
var s = e.selectedIndex;
if(s>0)
{
tab.rows[s - 1].style.display = "";
}
}
</SCRIPT>

[cpzhg]

谢谢meizz(梅花雪)大哥,可以了!

[meizz]

<select name="text" onChange="test_change(this)">
<option value="" selected>请选择</option>
<option value="1" selected>test1</option>
<option value="2" selected>test2</option>
<option value="3" selected>test3</option>
</select>

<table id="tab" border=1>
<tr style="display: none">
<td>test1</td>
</tr>

<tr style="display: none">
<td>test2</td>
</tr>

<tr style="display: none">
<td>test2</td>
</tr>

</table>

<SCRIPT LANGUAGE="JavaScript">
function test_change(e)
{
var tab = document.getElementById("tab");
for(var i=0; i<tab.rows.length; i++)
tab.rows[i].style.display = "none";
var s = e.value;
if(s!="")
{
tab.rows[parseInt(s, 10) - 1].style.display = "";
}
}
</SCRIPT>