How to make the value in dropdownlist not change after submit in JSP?

Question

Let's say i have a jsp page which contains a dropdownlist. when user select a item and click submit to submit the JSP page to itself, after that , the JSP page will reload and item selected before will disselected. How can i make it not change even after reload the JSP page?

Answer 1

Set the selected attribute of the option that was passed in to the form... your output should look like this (assuming the user selected "Saab"):

<select>
  <option>Volvo</option>
  <option selected="selected">Saab</option>
  <option>Mercedes</option>
  <option>Audi</option>
</select>

Answer 2

You have to re-select it.

So it will end up like this:

 <select name="dropdown">
 <%
       String selectedItem = request.getParameter("dropdown");
       for( String item : values ) {
 %>
       <option <%=item.equals(selectedItem)?selected:""%>><%=item%>

 <%
       }
 %>

That way each time you reload the jsp page, you verify if the current item you're painting is the same it was previously selected by the user. If so, you append "selected" to the option ( the first time it won't match anything )

I'm a bit rusty in JSP, so , probably there is a more "elegant" way to do it, but this "old-style" does works for sure.

I hope it helps.

Answer 3

I think this method is better:

<script type = "text/javascript"/>
<%String selectedItem ;
if(request.getAttribute("dropdown") != null){
  selected= request.getAttribute("dropdown");%>

document.getElementById("selectbox").selectedIndex = selectedItem;
<%}%>
</script>

I think this method will work.