xml parsing . want to access internet on emulator

i want  to get text  from text box (which is created in xaml dynamically )within list box,how cnamespace helloxml

  <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
           
            <ListBox Height="778" ItemsSource="{Binding}" HorizontalAlignment="Left" Margin="24,-45,0,0" Name="listBoxAuthors" VerticalAlignment="Top" Width="444" Loaded="listBox1_Loaded" SelectionChanged="listBoxAuthors_SelectionChanged">
                <phone:WebBrowser HorizontalAlignment="Center" Name="web" Margin="9,121,0,0" />
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Orientation="Horizontal">
                            <Image Source="{Binding AuthorImage}" Width="150" Stretch="UniformToFill" HorizontalAlignment="Center" />
                            <StackPanel Width="370">
                                <TextBlock Text="{Binding AuthorName}" FontWeight="Bold" FontSize="22"  Name="id"/>
                                <TextBlock Text="{Binding Description}" Name="name" />
                                <TextBlock x:Name="srctxtbox" Text="{Binding Source}" />
                                                         </StackPanel>
                        </StackPanel>
                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>
        </Grid>



 code behind it
    public partial class MainPage : PhoneApplicationPage
    {
        // Constructor
        public MainPage()
        {
            InitializeComponent();

            SupportedOrientations = SupportedPageOrientation.PortraitOrLandscape;
        }
        private void listBox1_Loaded(object sender, RoutedEventArgs e)
        {
            var element = XElement.Load("Authors.xml");
            var authors = from var in element.Descendants("Author")
                          orderby var.Attribute("AuthorName").Value
                          select new Authors
                              {
                                  AuthorId = Convert.ToInt32(var.Attribute("AuthorId").Value),
                                  AuthorName = var.Attribute("AuthorName").Value,
                                  AuthorImage = GetImage(var.Attribute("AuthorImage").Value),
                                  Description = var.Attribute("Description").Value,
                                  Source = var.Attribute("Source").Value
                              };

            listBoxAuthors.DataContext = authors;

        }
        public ImageSource GetImage(string path)
        {
            return new BitmapImage(new Uri(path, UriKind.RelativeOrAbsolute));
        }

        private void listBoxAuthors_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {

           var listBoxItem = listBoxAuthors.SelectedItem as ListBoxItem;
           TextBlock nameBlock = listBoxItem.FindName("srctxtbox") as TextBlock;
           MessageBox.Show(nameBlock.Text);
           
      
        }
    }an i get value please help me out