protected void ddlSection_SelectedIndexChanged(object sender, EventArgs e) { //Populated list of Roll numbers based on the Class and Section selected ddlRollNumber.DataSource = dbops.getRollNos(ddlClasses.SelectedValue, ddlSection.SelectedValue); ddlRollNumber.DataTextField = "roll_no"; ddlRollNumber.DataValueField = "roll_no"; ddlRollNumber.DataBind(); ddlRollNumber.Items.Insert(0, new ListItem("--Select Roll Number--", "0")); }