public override async Task <bool> LoadAsync()
{
var file = await ApplicationData.Current.LocalFolder.GetFileAsync(FILENAME);
var provider = new Windows.Security.Cryptography.DataProtection.DataProtectionProvider("LOCAL=user");
using (var stream = await file.OpenStreamForReadAsync().ConfigureAwait(false))
{
using (var reader = new BinaryReader(stream))
{
var length = reader.ReadInt32();
var cipher = reader.ReadBytes(length);
var plaintext = await provider.UnprotectAsync(cipher.AsBuffer()).AsTask().ConfigureAwait(false);
var bytes = plaintext.ToArray();
var json = Encoding.UTF8.GetString(bytes, 0, bytes.Length);
data = JsonToDictionary(json);
}
}
return(true);
}
public override async Task <bool> SaveAsync()
{
byte[] bytes = Encoding.UTF8.GetBytes(DictionaryToJson(data));
var provider = new Windows.Security.Cryptography.DataProtection.DataProtectionProvider("LOCAL=user");
var cipher = (await provider.ProtectAsync(bytes.AsBuffer()).AsTask().ConfigureAwait(false)).ToArray();
var localFolder = ApplicationData.Current.LocalFolder;
var file = await localFolder.CreateFileAsync(FILENAME, CreationCollisionOption.OpenIfExists).AsTask().ConfigureAwait(false);
using (var stream = await file.OpenStreamForWriteAsync().ConfigureAwait(false))
{
using (var writer = new BinaryWriter(stream))
{
writer.Write((Int32)cipher.Length);
writer.Write(cipher);
}
}
return(true);
}
