<script>
function show()
{
document.myfrm.sel2.selectedIndex=document.myfrm.sel.selectedIndex;
}
</script><form name="myfrm">
<select name="sel" onChange="show()">
<option>aaaa
<option>bbbb
<option>cccc
</select> <select name="sel2" >
<option>aaaa
<option>bbbb
<option>cccc
</select>
</form>
function show()
{
document.myfrm.sel2.selectedIndex=document.myfrm.sel.selectedIndex;
}
</script><form name="myfrm">
<select name="sel" onChange="show()">
<option>aaaa
<option>bbbb
<option>cccc
</select> <select name="sel2" >
<option>aaaa
<option>bbbb
<option>cccc
</select>
</form>
我第2个下拉框的文本必须是由第一个传过去的
function show()
{
document.myfrm.sel2.length=1;
document.myfrm.sel2.options(0).text=document.myfrm.sel.options(document.myfrm.sel.selectedIndex).text;
document.myfrm.sel2.options(0).value=document.myfrm.sel.options(document.myfrm.sel.selectedIndex).value;
}
</script><form name="myfrm">
<select name="sel" onChange="show()">
<option>aaaa
<option>bbbb
<option>cccc
</select><select name="sel2" >
<option>aaaa
<option>bbbb
<option>cccc
</select>
</form>