Button update for DropDownList added dinamically in GridView

Hello everybody. I find myself in difficulty and ask for help for a situation that is often treated, but separately, namely: DDL dynamically created in GridView and event external to GridView that takes some in value / Text ... x stored in the DB.

They are at the first experiences and the code I report often derives from something else found on the net.

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In a WebForm I drew a GridView. Outside the GridView is a Button.

The GridView is made up of 2 BoundFields (of which the first is not visible).

This is the page:

<% - -%>

<% - -%>

& nbsp; _______________________________________________________________________________________

& nbsp;

*********************************

In the page Load:

1. I "assume" n°2 DateTime variables that I will need to add the DropDownLists

2. "populate" the mysql oCombo DataTable that I will need for the combos

3. if (! This.IsPostBack) {

... "populate" the DataTable oDataTable_2 by filtering my table by x credentials and date range

... loop this DT x generate the TemplateFields. This is the code:

     for (int k = 2; k

     {

         TemplateField tfield = new TemplateField ();

         tfield = new TemplateField ();

         tfield.HeaderText = oDataTable_2.Columns [k] .ColumnName;

         tfield.ItemStyle.Width = 55;

         GridView2.Columns.Add (tfield);

      }

... I do the DataBind

}

4. This is the code:

protected void GridView_RowDataBound (Object sender, GridViewRowEventArgs e)

{

   if (e.Row.RowType == DataControlRowType.DataRow)

   {

      string NomeGiorno = "";

      for (int k = 2; k

      {

         NomeGiorno = oDataTable_2.Columns [k] .ColumnName.ToString ();

         DropDownList ddlCombo = new DropDownList ();

         ddlCombo.ID = NomeGiorno;

         ddlCombo.DataSource = oCombo;

         ddlCombo.DataTextField = oCombo.Columns [0] .ColumnName;

         ddlCombo.DataValueField = oCombo.Columns [0] .ColumnName;

         ddlCombo.DataBind ();

         string country = (e.Row.DataItem as DataRowView) .Row [DayName] .ToString ();

         ddlCombo.Width = 55;

         ddlCombo.Font.Name = "Arial";

         ddlCombo.Font.Size = 8;

         ddlCombo.Items.FindByText (country) .Selected = true;

         e.Row.Cells [k] .Controls.Add (ddlCombo);

      }

   }

GridView2.Columns [1] .HeaderStyle.CssClass = "locked";

}

So far everything ok (or at least outwardly). I use DDL, combining items ... everything OK!

But later I want to store the new situation in the DB and so I will have to build

the update query by cycling the columns of the GridView (which has only one row)

But I can't find control !!

I tried this code ...

protected void ButtonOK_Click (object sender, EventArgs e)

{

      string cStringa = "update schedule set";

      string NomeGiorno = "";

      for (int k = 2; k

      {// ie after tax code, surname and name.

         NomeGiorno = GridView2.Columns [k] .ToString ();

         string test = ((DropDownList) GridView2.Rows [0] .FindControl (NomeGiorno)). SelectedItem.Text;

         .....

         .....

      }

} 

I get the classic error:

System.NullReferenceException: 'Reference to an object not set on an object instance.'

Thanks to all those x will be able to give me a hand

Alessio