Selecting controls from a dynamically generated Grid View - asp.net

Question

Below is the code for a Grid View that I have. The Gird View is populated by a set of data returned from a database.
<asp:GridView ID="GridView1" runat="server" CellPadding="3" AutoGenerateColumns="False" EnableModelValidation="True">
<RowStyle BackColor="#000000" ForeColor="#8C4510" />
<FooterStyle BackColor="#000000" ForeColor="#8C4510" />
<PagerStyle ForeColor="#8C4510" HorizontalAlign="Center" />
<SelectedRowStyle BackColor="#000000" Font-Bold="True" ForeColor="White" />
<HeaderStyle BackColor="#FF9933" Font-Bold="True" ForeColor="Black" />
<Columns>
<asp:TemplateField HeaderText="Requestor">
<ItemTemplate>
<asp:Label ID="Requestor" runat="server" Text='<%# Bind("REQUESTED_BY") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Card Number">
<ItemTemplate>
<asp:Label ID="CardNumber" runat="server" Text='<%# Bind("CARD_NUMBER") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Date Submitted">
<ItemTemplate>
<asp:Label ID="DateSubmitted" runat="server" Text='<%# Bind("DATE_SUBMITTED") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Confirm?">
<ItemTemplate>
<asp:CheckBox ID="chkConfirm" runat="server" Checked='<%# Bind("EMAIL_SENT") %>' />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" />
When a box is ticked in the Grid View, users should then be able to press a button that calls the ConfirmCards_Click Sub.
Protected Sub ConfirmCards_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ConfirmCards.Click
Dim NumberOfRows = GridView1.Rows.Count
Dim i As Integer = 0
Dim ConfirmValue As CheckBox
Dim CardNumber As Label
Dim CardsConfirmed As String
Dim RunNumber As Integer = 0
For i = 0 To NumberOfRows - 1
ConfirmValue = GridView1.Rows(i).FindControl("chkConfirm")
CardNumber = GridView1.Rows(i).FindControl("CardNumber")
MsgBox(ConfirmValue.Checked & " " & CardNumber.Text, vbOKOnly, "Card and checked status")
Next
End Sub
In the actual system, this sub would have funcitonality that marks a field in a database, confirming that the cards have been confirmed.
However, when clicking the button that calls the ConfirmCards_Click sub, the alertbox always comes back with False and the CardNumber of the rows, regradless of whether or not chkConfirm has been ticked.
How can I fix this? I have very similar code in another page that works just fine - is there some setting that needs to be applied to the page in order for the server to realise that the checkboxes have been ticked?
Edit: Including Page_Load VB code, as requested.
Public Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim qryRaisedCards As String
If TeamName.Text = "Admin" Then
qryRaisedCards = "select CARD_NUMBER, REQUESTED_BY, DATE_SUBMITTED, EMAIL_SENT from SUBMISSIONS where EMAIL_SENT = 0 order by DATE_SUBMITTED, CARD_NUMBER"
Else
qryRaisedCards = "select CARD_NUMBER, REQUESTED_BY, DATE_SUBMITTED, EMAIL_SENT from SUBMISSIONS where EMAIL_SENT = 0 and TEAM_NAME = :TeamName order by DATE_SUBMITTED, CARD_NUMBER"
End If
Using cn2 As New OracleConnection(ConfigurationManager.ConnectionStrings("myConnectionString").ConnectionString), _
cmd2 As New OracleCommand(qryRaisedCards, cn2)
If TeamName.Text <> "Admin" Then
cmd2.Parameters.Add(":TeamName", OracleDbType.Varchar2, 60).Value = TeamName.Text
End If
Dim RaisedCardsAdapter As New OracleDataAdapter(cmd2)
Dim RaisedCardsDataset As New DataSet()
RaisedCardsAdapter.Fill(RaisedCardsDataset, "UserPermissions")
cn2.Open()
cmd2.ExecuteNonQuery()
cn2.Close()
If RaisedCardsDataset.Tables(0).Rows.Count > 0 Then
ErrorMessage.Visible = False
GridView1.DataSource = RaisedCardsDataset
GridView1.DataBind()
Else
GridViewPanel.Visible = False
ErrorMessage.Visible = True
ErrorMessage.Text = "There are no submitted cards that have not been confirmed at this time."
End If
End Using
End Sub

Answer 1

From code what I see is your gridview is getting bound on postback also. Which causes loosing value of state with which it was posted back. try wraping your code of Page_Load in If not IsPostback then.
Public Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim qryRaisedCards As String
If Not IsPostBack Then
If TeamName.Text = "Admin" Then
qryRaisedCards = "select CARD_NUMBER, REQUESTED_BY, DATE_SUBMITTED, EMAIL_SENT from SUBMISSIONS where EMAIL_SENT = 0 order by DATE_SUBMITTED, CARD_NUMBER"
Else
qryRaisedCards = "select CARD_NUMBER, REQUESTED_BY, DATE_SUBMITTED, EMAIL_SENT from SUBMISSIONS where EMAIL_SENT = 0 and TEAM_NAME = :TeamName order by DATE_SUBMITTED, CARD_NUMBER"
End If
Using cn2 As New OracleConnection(ConfigurationManager.ConnectionStrings("myConnectionString").ConnectionString), _
cmd2 As New OracleCommand(qryRaisedCards, cn2)
If TeamName.Text <> "Admin" Then
cmd2.Parameters.Add(":TeamName", OracleDbType.Varchar2, 60).Value = TeamName.Text
End If
Dim RaisedCardsAdapter As New OracleDataAdapter(cmd2)
Dim RaisedCardsDataset As New DataSet()
RaisedCardsAdapter.Fill(RaisedCardsDataset, "UserPermissions")
cn2.Open()
cmd2.ExecuteNonQuery()
cn2.Close()
If RaisedCardsDataset.Tables(0).Rows.Count > 0 Then
ErrorMessage.Visible = False
GridView1.DataSource = RaisedCardsDataset
GridView1.DataBind()
Else
GridViewPanel.Visible = False
ErrorMessage.Visible = True
ErrorMessage.Text = "There are no submitted cards that have not been confirmed at this time."
End If
End Using
End If
End Sub