WPF DataGrid 未在第一行更新

Question

I have a datagrid like that:

<DataGrid Margin="10" x:Name="datagrid1" Height="450" Width="1100">
                                <DataGrid.Columns>
                                    <DataGridTextColumn Width="200" Header="Starttime" Binding="{Binding xxx1}" />
                                    <DataGridTextColumn Width="130" Header="Enddtime" Binding="{Binding xxx2}" />
                                    <DataGridTextColumn Width="130" Header="Gesamte Pause" Binding="{Binding xxx3}" />                                        
                                    <DataGridTemplateColumn Width="130">
                                        <DataGridTemplateColumn.CellTemplate>
                                            <DataTemplate>
                                            <Button x:Name="button1" Width="80" Click="button1_Click">Urlaub/Feiertag</Button>
                                        </DataTemplate>
                                        </DataGridTemplateColumn.CellTemplate>
                                    </DataGridTemplateColumn>                                   
                                </DataGrid.Columns>                                  
                            </DataGrid>

Datagrid is filled from local .MDF Database like that

            string connString2 = @"Data Source=(localdb)\MSSQLLocalDB; AttachDbFilename=|DataDirectory|\LocalDatabase.mdf; Integrated Security=True;";
        SqlConnection MyConn = new SqlConnection(connString2);
        MyConn.Open();
        sqldatadapter1.SelectCommand = new SqlCommand("select * from mytable", MyConn);
        cmbl = new SqlCommandBuilder(sqldatadapter1);
        sqldatadapter1.Fill(table1);
        bindingSource1.DataSource = table1;
        datagrid1.ItemsSource = table1.DefaultView;

I now try to change specific rows by clicking the button1 that I implemented with DataGridTemplateColumn for each row.

  private void button1_Click(object sender, RoutedEventArgs e)
    {
        try
        {               
            DataRowView row = (DataRowView)datagrid1.SelectedItem;

            if (row[1].ToString() == "xxx1")
            {
                row[1] = "";
            }
            else
            {
                row[1] = "xxx1";
            }
         
            sqldatadapter1.Update((DataTable)bindingSource1.DataSource);
            CollectionViewSource.GetDefaultView(datagrid1.ItemsSource).Refresh();
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }
    }

However this works just fine for all rows except the first one. The text of the first row in my datagrid is changed like it is supposed to but my database entries are not updated for this specific row. For the second row everything works fine.

Answer 1

I found a workaround for myself. I just added a blank row for the first and last entry. After that I just hid those two rows with a Rowstyle like that:

<DataGrid.RowStyle>
                                    <Style TargetType="DataGridRow">
                                        <Style.Triggers>
                                            <DataTrigger Binding="{Binding starttime}" Value="leerzeile">
                                                <Setter Property="Visibility" Value="Collapsed" />
                                            </DataTrigger>
                                        </Style.Triggers>
                                    </Style>
                                </DataGrid.RowStyle>

Not perfect but working. :)