<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT="">
</HEAD>
<BODY>
<h3>select的增删改</h3><br>
双击修改
<form id="form1" name="form1" method="post" action="">
<p>
<select name="select" size="6">
<option value="computer">电脑</option>
<option value="inter">上网</option>
<option value="lvyou">旅游</option>
</select>
>>
<select name="s2" size="6" onDblClick="updateValue()">
</select>
</p>
<p> </p>
<p>
<input type="button" name="b13" value="<<" onClick="delValue()" />
<input type="button" name="b12" value=">>" onClick="addValue()" />
<br />
</p>
</form>
</BODY>
</HTML>
<SCRIPT LANGUAGE="JavaScript">
//添加
function addValue(){
o = document.getElementById("select");
for(c=0; c<o.length; c++){
if(o.options[c].selected){
var newOption = document.createElement("option");
newOption.value=o.options[c].value;
newOption.text=o.options[c].text;
form1.s2.options.add(newOption);
}
}
}
//删除
function delValue(){
o = document.getElementById("s2");
for(c=0; c<o.length; c++){
if(o.options[c].selected){
form1.s2.remove(o.selectedIndex);
}
}
}
//修改 双击则执行修改
function updateValue(){
o = document.getElementById("s2");
var cvalue = window.prompt("欢迎","请在此输入要修改的值。");
if(cvalue==null) return;
for(c=0; c<o.length; c++){
if(o.options[c].selected){
o.options[c].text = cvalue;
o.options[c].value = cvalue;
}
}
}
</SCRIPT>
