C#/WPF How can I read "Bindings" from a TextBox (Data gets from a SQL-Table)?

Question

I have a question. I search the problem but I didn't find a solution. Hope someone can help me.

I have a "DataGrid" and in this is a "DataGrid.RowDetailsTemplate". There are "Textbox" they show data from a list binding. And I want to change this data when I click on a button, but I cant read the Bindings so I cant change them. Hope someone know what I mean.

WPF code:

    <dxn:NavBarGroup Name="_navBarOverlay" Header="Benutzerübersicht">
            <Grid Style="{StaticResource GridStyleAccordion}">
                <DataGrid x:Name="userDataGrid" CanUserReorderColumns="True" CanUserResizeColumns="True" CanUserResizeRows="True" RowDetailsVisibilityMode="VisibleWhenSelected" IsReadOnly="True" AlternatingRowBackground="{DynamicResource WihaGrauB}" ColumnWidth="auto" ColumnHeaderHeight="30"   AutoGenerateColumns="False" Grid.Row="0"   Width="auto" Height="auto">
                    <DataGrid.Columns>
                        <DataGridTextColumn Header="Benutzer"  Binding="{Binding Name}" MinWidth="150" Width="2*" />
                        <DataGridTextColumn Header="OperatorID" Binding="{Binding OperatorID}" MinWidth="200" Width="3*"/>
                        <DataGridCheckBoxColumn Header="Aktiv" Binding="{Binding Aktiv}" MinWidth="50" Width="*"/>
                    </DataGrid.Columns>
                    <DataGrid.RowDetailsTemplate>
                        <DataTemplate>
                            <DockPanel>
                                <Image DockPanel.Dock="Left" Source="{Binding ImageUrl}" Height="30" Width="25" Margin="10,0,0,0"/>
                                <Grid Margin="10">
                                    <Grid.ColumnDefinitions>
                                        <ColumnDefinition Width="Auto"/>
                                        <ColumnDefinition Width="*"/>
                                    </Grid.ColumnDefinitions>
                                    <Grid.RowDefinitions>
                                        <RowDefinition Height="Auto"/>
                                        <RowDefinition Height="Auto"/>
                                        <RowDefinition Height="Auto"/>
                                        <RowDefinition Height="Auto"/>
                                        <RowDefinition Height="Auto"/>
                                        <RowDefinition Height="Auto"/>
                                        <RowDefinition Height="Auto"/>
                                    </Grid.RowDefinitions>
                                    <TextBlock Text="Name: " FontFamily="{DynamicResource WihaFontFamaly}" FontWeight="Bold" Grid.Row="1" Margin="2,2,2,2"/>
                                    <TextBox  x:Name="nameText" Text="{Binding  Path=Name, Mode=TwoWay}" Grid.Column="1" Width="150" TextAlignment="Center" HorizontalAlignment="Left" Grid.Row="1"  Margin="2,2,2,2"  />
                                    <TextBlock Text="OperatorID: " FontFamily="{DynamicResource WihaFontFamaly}" Grid.Row="2" FontWeight="Bold" Margin="2,2,2,2"/>
                                    <TextBox x:Name="operatorText" IsReadOnly="True" Text="{Binding OperatorID}" Width="150" HorizontalAlignment="Left" Grid.Row="2" Grid.Column="2" TextAlignment="Center"  Margin="2,2,2,2" />
                                    <TextBlock Text="DeviceID: " FontFamily="{DynamicResource WihaFontFamaly}" FontWeight="Bold" Grid.Row="3" Margin="2,2,2,2"/>
                                    <TextBox Text="{Binding DeviceID}" Grid.Column="3" Width="150" HorizontalAlignment="Left" Grid.Row="3" TextAlignment="Center"  Margin="2,2,2,2"/>
                                    <TextBlock Text="Passwort: " FontFamily="{DynamicResource WihaFontFamaly}" FontWeight="Bold" Grid.Row="4" Margin="2,2,2,2"/>
                                    <TextBox Text="{Binding Passwort}" Grid.Column="4" Width="150" HorizontalAlignment="Left" Grid.Row="4" TextAlignment="Center"   Margin="2,2,2,2"/>
                                    <TextBlock Text="Aktiv:" FontWeight="Bold" FontFamily="{DynamicResource WihaFontFamaly}" Grid.Row="5" Margin="2,2,2,2"/>
                                    <CheckBox Grid.Column="5" Grid.Row="5" IsChecked="{Binding Aktiv}" Margin="2,2,2,2" />
                                    <Button Style="{StaticResource ButtonStyleWIHA}" Click="saveUserPanel_Click" Name="saveUserPanel" Content="Save" Grid.Row="6" />
                                </Grid>
                            </DockPanel>
                        </DataTemplate>
                    </DataGrid.RowDetailsTemplate>
                </DataGrid>
            </Grid>
        </dxn:NavBarGroup>

C# code where the data comes:

     public void ShowAllOperator()
    {
        try
        {
            List<User> users = new List<User>();
            // string sql = "SELECT * FROM wiha_Operators";
            SqlConnection conn = new SqlConnection("Server=127.0.0.1;Database=Wiha;Trusted_Connection=true");
            conn.Open();
            // SqlCommand cmd = new SqlCommand(sql, conn);
            SqlCommand cmd = new SqlCommand("dbo.wiha_operators_SelectAll", conn);
            cmd.CommandType = CommandType.StoredProcedure;
            using (SqlDataReader rdr = cmd.ExecuteReader())
            {

                while (rdr.Read())
                {
                    users.Add(new User() { Name = rdr.GetValue(2).ToString(), OperatorID = rdr.GetValue(0).ToString(), Aktiv = rdr.GetValue(4).Equals(true), ImageUrl = "C:/Users/Jason/Desktop/DeleteIcon.png", DeviceID = rdr.GetValue(1).ToString(), Passwort = rdr.GetValue(3).ToString() });
                }

            }
            userDataGrid.ItemsSource = users;
        }
        catch (Exception)
        {

            throw;
        }
    }

Here I want to change them:

     private void saveUserPanel_Click(object sender, RoutedEventArgs e)
    {


    }

My User list:

     public class User
    {
        public string Name { get; set; }
        public string OperatorID { get; set; }
        public bool Aktiv { get; set; }
        public string ImageUrl { get; set; }
        public string DeviceID { get; set; }
        public string Passwort { get; set; }

    }

Hope you know what I want from you. You miss or didn't understand something? Ask me :)

EDIT

My new User class:

    public class User : INotifyPropertyChanged
    {
        private string _name = string.Empty;
        public event PropertyChangedEventHandler PropertyChanged;
        public string Name
        {
            get { return this._name; }
            set
            {
                if (value != this._name)
                {
                    this._name = value;
                    NotifyPropertyChanged();
                }
            }
        }
        public string OperatorID { get; set; }
        public bool Aktiv { get; set; }
        public string ImageUrl { get; set; }
        public string DeviceID { get; set; }
        public string Passwort { get; set; }

        private void NotifyPropertyChanged([CallerMemberName] String propertyName = "")
        {
            if (PropertyChanged != null)
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }

I see only the old value.

Answer 1

As @Ash suggests, you could use the DataContext of the Button, which is a User object, to access the Item, since it is part of the DataTemplate

private void saveUserPanel_Click(object sender, RoutedEventArgs e)
{
  var user = (sender as Button).DataContext as User;
  if(user != null)
  {
    user.Name = "NewName";
    var active = user.Aktiv;
    // ...
  }
}

Notice that updating the user object in the code behind will not update your UI since Userdoes not implement INotifyPropertyChanged.