Displaying value second drop down based on the value selected in the first drop down

[Latha Kota]

I have two drop down lists. Based on the value selected in the first drop down, the values in the second should pop up. And these values have to come from database. Can anyone help me how to do this plz.

[Mark Howard]

Hi Latha
I'm no expert on this, but I'd think you would need to pass your request with the selection made in the first drop-down to a servlet, the servlet would in turn retrieve the appropriate data from the database based on that value, and then pass control to the JSP page to render this retrieved data in the 2nd drop-down.
The retrieved database data could be stored by the servlet in a Java Bean, and used as such (ie. jsp:useBean) in the JSP. Or the servlet could store the retrieved data as an Enumeration object of the database values, and the JSP could iterate through the Enumeration object to build the 2nd drop-down list. Presumably the Bean or Attribute objects would be in session scope as they are specific to a particular user.
Hope this helps

[Geeta Ramasami]

Hi,
In the OnChange event of the first combo box, call a javascript function.
In that Function just have the code to submit the page.U can submit the request to the same JSP page.U can retrieve the combo box value and call a beans method by passing the combobox value as a paremter to the method.
Use JSP usebean tag.
ie

  
<%
   String firstComboValue = request.getParameter("combo")
%>
<jsp:useBean id="dataGet" scope="Request" class="beanclass">
<%
     if(comboValue != null)
     {
        arrList = (ArrayList)dataGet.retrieveComboValue(firstComboValue)
     }   
%>

where arrList would be an arrayList
Iterate the arrList and populte the second combo box..
Implement the database access logic in the bean.
Hope this helps
Cheers
Geeta