i need to validate the dates when editing a datagrid

[tmashley]

Hello, i need to validate the DateTime field that is entered when editing data within a datagrid.

i have a web application written in vb.net

my datagrid: - aspx

<aspataGrid
Runat="Server"
ID="Datagrid1"
OnCancelCommand="CancelCommand"
OnDeleteCommand="DeleteCommand"
OnUpdateCommand="UpdateCommand"
OnEditCommand="EditCommand">
<Columns>
<asp:TemplateColumn Visible="False"> 'Used as key
<ItemTemplate>
<asp:Label ID="lblStartDate" Text='<%# DataBinder.Eval(Container.DataItem,"StartDate") %>' Runat="server" />
</ItemTemplate>
</asp:TemplateColumn>
<asp:BoundColumn DataField="StartDate"></asp:BoundColumn>
<asp:BoundColumn DataField="EndDate"></asp:BoundColumn>
<asp:BoundColumn DataField="Operator"></asp:BoundColumn>
<asp:EditCommandColumn ItemStyle-Width="120" ButtonType="LinkButton" CancelText="Cancel" EditText="Edit" UpdateText="Update"></asp:EditCommandColumn>
<asp:TemplateColumn ItemStyle-Width="80" ItemStyle-HorizontalAlign="Center">
<ItemTemplate>
<asp:CheckBox ID="chkSelection" Runat="server" />
</ItemTemplate>
</asp:TemplateColumn>

</Columns>
</aspataGrid>


my datagrid: - code behind

 
    Sub MyDataGrid_EditCommand(ByVal s As Object, ByVal e As DataGridCommandEventArgs)
        dgdBurnOffTimeEdit.EditItemIndex = e.Item.ItemIndex
        tblNotes.Visible = True
        BindData()
    End Sub
    Sub MyDataGrid_Cancel(ByVal Source As Object, ByVal E As DataGridCommandEventArgs)
        dgdBurnOffTimeEdit.EditItemIndex = -1
        BindData()
        tblNotes.Visible = False
    End Sub
    Sub MyDataGrid_UpdateCommand(ByVal s As Object, ByVal e As DataGridCommandEventArgs)
        Dim tID = dgdBurnOffTimeEdit.DataKeys(CInt(e.Item.ItemIndex))
        Dim tStartDate As TextBox = e.Item.Cells(1).Controls(0)
        Dim tEndDate As TextBox = e.Item.Cells(2).Controls(0)
        Dim tOperator As TextBox = e.Item.Cells(3).Controls(0)

        strStart = FormatDateTime(CDate(tStartDate.Text), 1) & " " & FormatDateTime(CDate(tStartDate.Text), 4)
        strEnd = FormatDateTime(CDate(tEndDate.Text), 1) & " " & FormatDateTime(CDate(tEndDate.Text), 4)
        Dim ID = FormatDateTime(CDate(tID), 1) & " " & FormatDateTime(CDate(tID), 4)

        Dim MySDate As Date = strStart
        Dim MyEDate As Date = strEnd

        Dim ts As TimeSpan = MyEDate.Subtract(MySDate)
        Dim Minutes = ts.TotalMinutes

        If Minutes > 5 Then
            Exit Sub
        Else
            ws.Credentials = System.Net.CredentialCache.DefaultCredentials
            ws.BurnOffInsert(strStart, strEnd, tOperator.Text, ID)

            dgdBurnOffTimeEdit.EditItemIndex = -1
            BindData()
        End If
        tblNotes.Visible = False
    End Sub
    Sub MyDataGrid_DeleteCommand(ByVal s As Object, ByVal e As DataGridCommandEventArgs)
        Dim txtID = dgdBurnOffTimeEdit.DataKeys(CInt(e.Item.ItemIndex))
        Dim ID = FormatDateTime(CDate(txtID), 1) & " " & FormatDateTime(CDate(txtID), 4)
        ws.Credentials = System.Net.CredentialCache.DefaultCredentials
        ws.BurnOffDelete(ID)
        BindData()
    End Sub