1
<html>
2 <body>
3 <form name="aa">
4 <table align="center">
5 <tr>
6 <td>
7 <select name="xuanze" size="6" style="80px">
8 <option value="海淀">海淀</option>
9 <option value="朝阳">朝阳</option>
10 <option value="东城">东城</option>
11 <option value="西城">西城</option>
12 <option value="宣武">宣武</option>
13 <option value="丰台">丰台</option>
14 </select>
15 </td>
16 <td align="center">
17 <input type="button" value="添加>>" onclick="javascript:add()"/>
18 <br>
19 <input type="button" value="<<删除" onclick="javascript:del()"/>
20 </td>
21 <td>
22 <select name="xuanzhong" size="6" style="80px"></select>
23 </td>
24 </tr>
25
26 </table>
27</form>
28 </body>
29 <script type="text/javascript">
30
function isexist(va){
31
var ee = false;
32 for(var i=0;i<document.aa.xuanzhong.options.length;i++)
33 if(document.aa.xuanzhong.options[i].value==va)
34
{ ee=true; break;}
35 return ee;
36
}
37 function add(){//添加
38 for(var i=0;i<document.aa.xuanze.options.length;i++)
39 if(document.aa.xuanze.options[i].selected) {
40 if(!isexist(document.aa.xuanze.options[i].value)) //是否已经添加？？
41 document.aa.xuanzhong.options[document.aa.xuanzhong.options.length]
42 = new Option(document.aa.xuanze.options[i].value,document.aa.xuanze.options[i].text);
43
}
44 }
45 function del(){
46 for(var i=document.aa.xuanzhong.options.length-1;i>=0;i--)
47 if(document.aa.xuanzhong.options[i].selected)
48 document.aa.xuanzhong.options[i] = null; //删除一个项目
49
50 }
51 </script>
52</html>
<html>2
<body>3
<form name="aa">4
<table align="center">5
<tr>6
<td>7
<select name="xuanze" size="6" style="80px">8
<option value="海淀">海淀</option>9
<option value="朝阳">朝阳</option>10
<option value="东城">东城</option>11
<option value="西城">西城</option>12
<option value="宣武">宣武</option>13
<option value="丰台">丰台</option>14
</select>15
</td>16
<td align="center">17
<input type="button" value="添加>>" onclick="javascript:add()"/>18
<br>19
<input type="button" value="<<删除" onclick="javascript:del()"/>20
</td>21
<td>22
<select name="xuanzhong" size="6" style="80px"></select>23
</td>24
</tr>25
26
</table>27
</form>28
</body>29
<script type="text/javascript">30
function isexist(va){
function isexist(va)
31
var ee = false;32
for(var i=0;i<document.aa.xuanzhong.options.length;i++)33
if(document.aa.xuanzhong.options[i].value==va)34
{ ee=true; break;}
35
return ee;36
}37
function add(){//添加38
for(var i=0;i<document.aa.xuanze.options.length;i++)39
if(document.aa.xuanze.options[i].selected) {40
if(!isexist(document.aa.xuanze.options[i].value)) //是否已经添加？？41
document.aa.xuanzhong.options[document.aa.xuanzhong.options.length]42
= new Option(document.aa.xuanze.options[i].value,document.aa.xuanze.options[i].text);43
}44
}45
function del(){46
for(var i=document.aa.xuanzhong.options.length-1;i>=0;i--)47
if(document.aa.xuanzhong.options[i].selected)48
document.aa.xuanzhong.options[i] = null; //删除一个项目49
50
}51
</script>52
</html>