write.cs

private async Task RaiseEvent(BankAccountEvent evnt)
{
    base.RaiseEvent(evnt);
    await ConfirmEvents();

    await _conn.AppendToStreamAsync(_stream, Version - 2, ToEventData(Guid.NewGuid(), evnt, new Dictionary<string, object>()));
}

private static EventData ToEventData(Guid eventId, object evnt, IDictionary<string, object> headers)
{
    var data = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(evnt));

    var eventHeaders = new Dictionary<string, object>(headers)
    {
        {
            "EventClrType", evnt.GetType().AssemblyQualifiedName
        }
    };
    var metadata = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(eventHeaders));
    var typeName = evnt.GetType().Name;

    return new EventData(eventId, typeName, true, data, metadata);
}

private static object DeserializeEvent(RecordedEvent evntData)
{
    var eventClrTypeName = JObject.Parse(Encoding.UTF8.GetString(evntData.Metadata)).Property("EventClrType").Value;
    return JsonConvert.DeserializeObject(Encoding.UTF8.GetString(evntData.Data), Type.GetType((string)eventClrTypeName));
}