WebPart drop down values working fine on PostBack in Dev. Environment (Single Machine) not in Farm

Question

We have three drop downs (ddlRotation, ddlOnCallType and ddlHospital) in our webpart. All values are being populated dynamically. One from list (ddlHospital) and other from tool part properties. For dropdown populated from list, we are storing values  in
View State.
WebPart is working fine in development environment (single  machine) while on production ( 1 front end, 1 index and 1 db server), drop down values disappear after post back. Below is the code.
protected void Page_Load(object sender, EventArgs e)
try
if (!Page.IsPostBack)
LoadData();
if (!string.IsNullOrEmpty(webPart._rotationDetail))
ddlRotation.Items.Add(new ListItem("All", "0"));
int i = 1;
string[] strRotationDetail = webPart._rotationDetail.Split(':');
foreach (string str in strRotationDetail)
ddlRotation.Items.Add(new ListItem(str, i.ToString()));
i++;
if (!string.IsNullOrEmpty(webPart._onCallTypes))
ddlOnCallType.Items.Add(new ListItem("All", "0"));
int j = 1;
string[] strOnCallTypes = webPart._onCallTypes.Split(':');
foreach (string str in strOnCallTypes)
ddlOnCallType.Items.Add(new ListItem(str, j.ToString()));
j++;
catch (Exception ex)
private void LoadData()
SPSecurity.RunWithElevatedPrivileges(delegate()
using (SPSite spSite = new SPSite("SITE_URL"))
using (SPWeb spWeb = spSite.OpenWeb())
SPList oList = spWeb.Lists[webPart.destListName];
SPListItemCollection setuplistItems = oList.Items;
if (setuplistItems != null && setuplistItems.Count > 0)
DataTable dtSetupData = setuplistItems.GetDataTable();
if (ViewState["SetupData"] != null)
ViewState.Remove("SetupData");
ViewState.Add("SetupData", dtSetupData);
else
ViewState.Add("SetupData", dtSetupData);
LoadHospitalCombo();
dateControl.SelectedDate = DateTime.Now;
else
// some error message
private void LoadHospitalCombo()
if (ViewState["SetupData"] != null)
DataTable dt = (DataTable)ViewState["SetupData"];
DataView dv = dt.DefaultView;
ddlHospital.Items.Clear();
ddlHospital.DataTextField = "TITLE";
ddlHospital.DataValueField = "TITLE";
ddlHospital.DataSource = dv.ToTable(true, "TITLE");
ddlHospital.DataBind();
ddlHospital.Items.Insert(0, "All");
Any help?
http://farhanfaiz.wordpress.com

Answer 1

Running your code in try/catch and doing nothing on exception, is not a good idea. Please try to put logging in your code as I believe your code is throwing exception. It's difficult to say seeing such a code what's wrong. Maybe the list doesn't exist or
exists with different name/title, or viewstate is disabled or webpart properties are not populated... there's so many possibilities. Also if possible refactor your code as shown below:
//Your Code, you are loading all items from database and then counting it
SPListItemCollection setuplistItems = oList.Items;
if (setuplistItems != null && setuplistItems.Count > 0)
//Refactored Code
if (oList.ItemCount > 0)
Thanks,
Sohel Rana
http://ranaictiu-technicalblog.blogspot.com