public static async Task RestoreAsync()
{
_sessionState = new Dictionary<String, Object>();
// Get the input stream for the SessionState file
StorageFile file = await ApplicationData.Current.LocalFolder.GetFileAsync(sessionStateFilename);
using (IInputStream inStream = await file.OpenSequentialReadAsync())
{
// Deserialize the Session State
DataContractSerializer serializer = new DataContractSerializer(typeof(Dictionary<string, object>), _knownTypes);
_sessionState = (Dictionary<string, object>)serializer.ReadObject(inStream.AsStreamForRead());
}
// Restore any registered frames to their saved state
foreach (var weakFrameReference in _registeredFrames)
{
Frame frame;
if (weakFrameReference.TryGetTarget(out frame))
{
frame.ClearValue(FrameSessionStateProperty);
RestoreFrameNavigationState(frame);
}
}
}