连动html(select)标签操作 原创（create by le)

 代码是最好的解释，请看代码，呵呵！

  function ChangeCustomId(obj) {
            var opt = obj.options[obj.selectedIndex]
            //alert("The option you select is:" + opt.text + "(" + opt.value + ")");
 
            var opt = obj.options[obj.selectedIndex]
            var selectItem = document.getElementsByName("mySelect1");
            for (i = 0; i < selectItem.length; i++) {
                selectItem[i].selectedIndex = obj.selectedIndex;
            }
        }
<select id="mySelect" name="mySelect" onchange="ChangeCustomId(this)"><option>1</option>
<option>4</option>
<option>5</option>
<option>6</option>
<option>9</option>
<option>10</option>
<option>14</option>
<option>15</option>
<option>16</option>
</select>
            </th>

function ChangeCustomId(obj) {
            var opt = obj.options[obj.selectedIndex]
            //alert("The option you select is:" + opt.text + "(" + opt.value + ")");

            var opt = obj.options[obj.selectedIndex]
            var selectItem = document.getElementsByName("mySelect1");
            for (i = 0; i < selectItem.length; i++) {
                selectItem[i].selectedIndex = obj.selectedIndex;
            }
        }