关于multiple select

Question

<select name="SelPG" id="SelPG" style="WIDTH:160px;">
          <option value="">测试</option>
          <%
  If request.QueryString("SelSecond")<>"" Then
do until oradynaset3.eof
response.write( "<option value=" & oradynaset3("code").value & ">" & oradynaset3("NAME").value & "</option>")
oradynaset3.dbmovenext
Loop
  End If
     %>
        </select>

Answer 1

<select id=sel multiple></select>
<input type=button onclick='document.getElementById("sel").options.add(new Option("text","value"));' value='aaaaa'>

Answer 2

function add(){
   var objOption = document.createElement("OPTION");
   objOption.value="234";
   objOption.innerHTML= "234";
   sel.appendChild(objOption);
}