简单的孤立存储问题

Question

I am trying to do a simple test with Isolated Storage so I can use it for a Windows Phone 7 application I am making.

The test I am creating sets a creates a key and value with one button, and with the other button sets that value equal to a TextBlock's text.

namespace IsoStore
{
public partial class MainPage : PhoneApplicationPage
{
    // Constructor
    public MainPage()
    {
        InitializeComponent();
    }

    public class AppSettings
    {
        IsolatedStorageSettings appSettings = IsolatedStorageSettings.ApplicationSettings;

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            appSettings.Add("email", "someone@somewhere.com");
        }

        private void button2_Click(object sender, RoutedEventArgs e)
        {
            textBlock1.Text = (string)appSettings["email"];
        }
    }      
}
}

This way gives me this error:

Cannot access a non-static member of outer type 'IsoStore.MainPage' via nested type 'IsoStore.MainPage.AppSettings'

So I tried this:

namespace IsoStore
{
public partial class MainPage : PhoneApplicationPage
{
    // Constructor
    public MainPage()
    {
        InitializeComponent();
    }

    public class AppSettings
    {
        IsolatedStorageSettings appSettings = IsolatedStorageSettings.ApplicationSettings;

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            appSettings.Add("email", "someone@somewhere.com");
        }

    }

    private void button2_Click(object sender, RoutedEventArgs e)
    {
        textBlock1.Text = (string)appSettings["email"];
    }
}
}

And instead I get this error:

The name 'appSettings' does not exist in the current context

So what obvious problem am I overlooking here?

Thanks so much for your time.

Answer 1

appSettings is out of scope for button2_Click

Update Since IsolatedStorageSettings.ApplicationSettings is Static anyway there's no need for the reference at all. Just directly access it.

namespace IsoStore
{

 public partial class MainPage : PhoneApplicationPage
 {


    // Constructor
    public MainPage()
    {
    InitializeComponent();


    }


    private void button1_Click(object sender, RoutedEventArgs e)
    {
    IsolatedStorageSettings.ApplicationSettings.Add("email", "someone@somewhere.com");
    }



    private void button2_Click(object sender, RoutedEventArgs e)
    {
       textBlock1.Text = (string)IsolatedStorageSettings.ApplicationSettings["email"];
    }
  }
}

Answer 2

Try this code, as there isn't any need to define AppSettings class.

namespace IsoStore
{
    public partial class MainPage : PhoneApplicationPage
    {
        IsolatedStorageSettings appSettings;

        // Constructor
        public MainPage()
        {
            InitializeComponent();
            appSettings = IsolatedStorageSettings.ApplicationSettings;
        }

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            appSettings.Add("email", "someone@somewhere.com");
        }

        private void button2_Click(object sender, RoutedEventArgs e)
        {
            textBlock1.Text = (string)appSettings["email"];
        }
    }
}