Question

I have a Windows 8 application. This application has several custom-defined classes. I need to store instances of these instances into Isolated Storage. From my understanding, Isolated Storage has been replaced with ApplicationDataContainer. Currently, I’m trying the following:

public class MyClass
{
  private HttpClient service = new HttpClient();

  public string FirstName { get; set; }

  public DateTime? BirthDate { get; set; }

  public int Gender { get; set; }

  public async Task Save()
  {
    // Do stuff...
  }
}

...

MyClass myInstance = new MyInstance();
// do stuff...

try {
  ApplicationDataContainer storage = ApplicationData.Current.LocalSettings;
  if (storage != null)
  {
    if (storage.Values.ContainsKey("MyKey"))
      storage.Values["MyKey"] = myInstance;
    else
      storage.Values.Add("MyKey", myInstance);
  }
} catch (Exception ex)
{
  MessageDialog dialog = new MessageDialog("Unable to save to isolated storage");
  dialog.ShowAsync();
}

What am I missing. Why is an exception always being thrown. The exception is not very descriptive. Its just a generic System.Exception and the message doesn’t help either. Can someone please help me?

Thank you

Answer 1

The exception I get from the code above seems pretty clear:

Data of this type is not supported.

Per Accessing app data with the Windows Runtime

The Windows Runtime data types are supported for app settings.

Note that there is no binary type. If you need to store binary data, use an application file.

You can use the ApplicationDataCompositeValue class to group settings that must be treated atomically (but they still need to be supported runtime data types). Scenario 4 of the Application Data Sample covers this.

In your specific case though, you may want to consider serializing to a file and using app file storage versus settings.