asked on

Control reference lost.

lstEvalItemName is a ListBox.

Code behind:

lstEvalItemName = FindControl("lstEvalItemName") as ListBox;

     private void FillEvalItemNameList()
        {
            lstEvalItemName.Items.Clear();

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Runtime error:

HResult=-2147467261
Message=Object reference not set to an instance of an object.
Source=StockProNew
StackTrace:
at StockProNew.Default1.FillEvalItemNameList() in c:\Users\Dovberman\Documents\Visual Studio 2012\Projects\StockProNew\StockProNew\Default1.aspx.cs:line 298
at StockProNew.Default1.Page_Load(Object sender, EventArgs e) in c:\Users\Dovberman\Documents\Visual Studio 2012\Projects\StockProNew\StockProNew\Default1.aspx.cs:line 158
at System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e)
at System.Web.UI.Control.OnLoad(EventArgs e)
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
InnerException:

I changed it to:

ListBox lstEvalItemName = new ListBox();
lstEvalItemName.Items.Clear();

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Why was this necessary?

Thanks,

Dovberman

ASKER

There is no error.

However the listbox does not get populated.

private void FillEvalItemNameList()
{
lstEvalItemName = FindControl("lstEvalItemName") as ListBox;
lstEvalItemName.Items.Clear();

string selectSQL = "SELECT EvalItemID, EvalItemName FROM EvalItems WHERE isActive = 1 ORDER BY EvalItemName";

string strConnection = connString.ToString();

SqlConnection conStockSelect = new SqlConnection(strConnection);

// Try to open the connection.
conStockSelect.Open();

SqlCommand cmd = new SqlCommand(selectSQL, conStockSelect);
lstEvalItemName.DataSource = cmd.ExecuteReader();
lstEvalItemName.DataTextField = "EvalItemName";
lstEvalItemName.DataValueField = "EvalItemID";
lstEvalItemName.DataBind();
conStockSelect.Close();
cmd.Dispose();
}

The connection opens.

The string selectSQL returns 9 rows in the SQL Server query as expected.

ASKER CERTIFIED SOLUTION

Craig Wagner

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Dovberman

ASKER

It's my mistake. I should have created a new project by selecting the Webform instead of the empty website project type.