select的onchange事件
<select name="Customerid" class="textfiled" onchange="this.Billingaddress=value">
<%
Set rs= Server.CreateObject("ADODB.Recordset")
Sql = "Select * From Customer"
rs.Open Sql,Conn,1,1
While Not rs.Eof
Response.Write "<option value="&rs("CustomerID")&""
If rs("CustomerID")=Cint(Request("Customerid")) Then response.Write "selected"
Response.Write ">"&rs("Companyname")&"</option>"
rs.MoveNext
Wend
rs.Close
Set rs=Nothing
%>
</select>
<input type="text" name="Billingaddress" value="">
上面已实现了把customerid的值放到Billingaddress文本框里,但是我要的是把customerid对应的companyname的值放到Billingaddress文本框里,该如何更改?