如何将位图图像插入Windows phone8.1 c#上的sqlite数据库

using SQLite;
using Windows.Storage;

public class Image
{
    [PrimaryKey, AutoIncrement]
    public int Id { get; set; }
    public string FileName { get; set; }
    public byte[] Data { get; set; }
}

public async Task CreateDatabase()
{
    StorageFolder localFolder = ApplicationData.Current.LocalFolder;
    StorageFile databaseFile = await localFolder.CreateFileAsync("mydatabase.db", CreationCollisionOption.OpenIfExists);
    SQLiteConnection connection = new SQLiteConnection(databaseFile.Path);
    connection.CreateTable<Image>();
}

using Windows.Storage.Streams;
using Windows.UI.Xaml.Media.Imaging;

public async Task<byte[]> ConvertBitmapToByteArray(WriteableBitmap bitmap)
{
    using (InMemoryRandomAccessStream stream = new InMemoryRandomAccessStream())
    {
        BitmapEncoder encoder = await BitmapEncoder.CreateAsync(BitmapEncoder.PngEncoderId, stream);
        encoder.SetPixelData(BitmapPixelFormat.Bgra8, BitmapAlphaMode.Ignore, (uint)bitmap.PixelWidth, (uint)bitmap.PixelHeight, 96, 96, bitmap.PixelBuffer.ToArray());
        await encoder.FlushAsync();
        stream.Seek(0);
        using (DataReader reader = new DataReader(stream))
        {
            byte[] data = new byte[stream.Size];
            await reader.LoadAsync((uint)stream.Size);
            reader.ReadBytes(data);
            return data;
        }
    }
}

public async Task InsertImage(string fileName, byte[] data)
{
    StorageFolder localFolder = ApplicationData.Current.LocalFolder;
    StorageFile databaseFile = await localFolder.GetFileAsync("mydatabase.db");
    SQLiteConnection connection = new SQLiteConnection(databaseFile.Path);
    Image image = new Image
    {
        FileName = fileName,
        Data = data
    };
    connection.Insert(image);
}

WriteableBitmap bitmap = // 获取位图图像
string fileName = "image.png";
byte[] data = await ConvertBitmapToByteArray(bitmap);
await InsertImage(fileName, data);