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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
 <head>
  <title> new document </title>
  <meta name="generator" content="editplus" />
  <meta name="author" content="[email protected]" />
  <meta name="keywords" content="javascript" />
  <meta name="description" content="for javascript region of csdn" />
 </head> <body>
    <form name="form2">
<select name="FriendList" size="3">
    <option value="1">calico</option>
    <option value="2">tortie</option>
    <option value="3">siamese</option>
</select>
<input type="button" id="btnAdd" value="Add >>" onclick="AddUser_Click()" />
<select name="ChatList" size="3">
</select>
    </form>
  <script type="text/javascript">
  <!--
function AddUser_Click()
{
    for (var i=0 ; i<=form2.FriendList.options.length -1 ; i++)
    {
        if (form2.FriendList.options[i].selected )
        {
            form2.ChatList.options.add(new Option(form2.FriendList.options[i].text, form2.FriendList.options[i].value));
            form2.FriendList.options.remove(i);
        }
    }
}    
  //-->
  </script>
 </body>
</html>