have radiobutton list filling strings , know how in given time value of selected element , throw string example. command selectedvalue , selecteditem have null values.
this radio button list filled several times during execution of same page.
//where fill radiobuttonlist public void mostraimagenscarrefadas() { list<string> files = new manfile().getlistfilesfordirectory(this, mae.diretorio_temp_img); rbimagemprincipal.items.clear(); if (files != null) { foreach (string item in files) { rbimagemprincipal.items.add(new listitem(item)); } } } //as in aspx <div> <asp:radiobuttonlist id="rbimagemprincipal" runat="server" repeatdirection="vertical" autopostback="false" onselectedindexchanged="rbimagemprincipal_selectedindexchanged"></asp:radiobuttonlist> //where encounter null values when trying selected item (clicked) //nothing value obtained direferente null. if (rbimagemprincipal.selecteditem != null) { if (rbimagemprincipal.selecteditem.tostring() == str) { imagem.imagemprincipal = "sim"; } }
it seems you're populating radiobuttonlist on page load - if - make sure surround population of radiobuttonlist if/then/postback block: if not page.ispostback ' populate rbl end if
eg:
if (!ispostback) { loadradiobuttonlist(); } 