asp.net - My RadioButtonList won't append Query String or show selected value after Postback - C# & .Net -

i have 2 issues. on aspx page, have 3 radiobuttonlists (aka rbl)that gets each of data database table. upon selection on rbl, postback occurs same page , value of specific rbl gets entered querystring, listview looking for, filter out products based on querystring. list view works fine when reads querystring filters list down.

issue 1 - on postback, value selected of 3 rbl's, doesn't selected when page loads. rbl's don't have value, if have default value set on page. how page reload values selected in rbl's you've chosen?

issue 2 - if make selection on of other 2 rbl's, instead of updating querystring, wipes out first value when posts again. if pick in rbl-1, posts specific field updated in querystring, if pick in rbl-2, posts value rbl-2, , wipes out value picked rbl-1. how can page load, while keeping of prior selections in querystring?

aspx code:         <p>normally open or closed:<asp:radiobuttonlist id="radiobuttonlist1" runat="server" enableviewstate="true"                  autopostback="true" datasourceid="normalitysds" datatextfield="op"                 datavaluefield="op" onselectedindexchanged="radiobuttonalllists_selectedindexchanged">             </asp:radiobuttonlist>             <asp:sqldatasource id="normalitysds" runat="server"                  connectionstring="<%$ 005 %>"                  selectcommand="select distinct [op] [matrix] order [op]">             </asp:sqldatasource>         </p>         <p>sizes:<asp:radiobuttonlist id="radiobuttonlist2" runat="server" enableviewstate="true"                  autopostback="true" datasourceid="sizessds" datatextfield="size" repeatcolumns="2"                  datavaluefield="size" onselectedindexchanged="radiobuttonalllists_selectedindexchanged">             </asp:radiobuttonlist>             <asp:sqldatasource id="sizessds" runat="server"                  connectionstring="<%$ 005 %>"                  selectcommand="select distinct [size] [matrix] order [size]">             </asp:sqldatasource>         </p>         <p>body:<asp:radiobuttonlist id="radiobuttonlist3" runat="server" enableviewstate="true"                  autopostback="true" datasourceid="bodysds" datatextfield="body"                  datavaluefield="body" onselectedindexchanged="radiobuttonalllists_selectedindexchanged">             </asp:radiobuttonlist>             <asp:sqldatasource id="bodysds" runat="server"                  connectionstring="<%$ 005 %>"                  selectcommand="select distinct [body] [matrix] order [body]">             </asp:sqldatasource>       <selectparameters>                     <asp:querystringparameter defaultvalue="nc" name="op" querystringfield="op" type="string" />                     <asp:querystringparameter defaultvalue="0.25" name="sz" querystringfield="sz" type="string" />                     <asp:querystringparameter defaultvalue="304" name="body" querystringfield="body" type="string" />       </selectparameters> 

code-behind:

using system; using system.collections.generic; using system.linq; using system.web; using system.web.ui; using system.web.ui.webcontrols;  namespace configurator {     public partial class product_config_full_wquery : system.web.ui.page     {         string baseurl = "/product_config_full_wquery.aspx";         string op;         string op2;         string sz;         string body;          protected void page_load(object sender, eventargs e)         {             if (!page.ispostback)             {                 op = (server.urldecode(request.querystring["op"] ));                 radiobuttonlist1.selectedindex = op2;                 radiobuttonlist1.databind();                   sz = server.urldecode(request.querystring["sz"]);                 body = server.urldecode(request.querystring["body"]);             }         }           // combining actions single protected-event         protected void radiobuttonalllists_selectedindexchanged(object sender, eventargs e)         {             op = radiobuttonlist1.selectedvalue.tostring();             sz = radiobuttonlist2.selectedvalue.tostring();             body = radiobuttonlist3.selectedvalue.tostring();              if (op != null)             {                 baseurl += "?op=" + op + "&";             }             //else op = "nc";              if (sz != null)             {                 baseurl += "sz=" + sz + "&";             }              if (body != null)             {                 baseurl += "body=" + body + "&";             }             response.redirect(string.format(baseurl, server.urlencode(op), server.urlencode(sz), server.urlencode(body)));         } 

since you're dynamically setting values inside radio button list, values page setting controls aren't there on postback (page lifecycle trying set values controls before data sources retrieve possible values , add items control itself).

also, stop using querystring hold postback values - if need to, set hiddenfields hold information, persist through postbacks , won't have worry odd querystring issues