Przechowywanie czasu Utc i lokalnego w Mongo

W ten sposób zmuszam MongoDB do przechowywania surowej wartości i ignoruje atrybut DateTimeKind w obiekcie DateTime.

Może to nie dotyczyć Twojej logiki biznesowej, ale ma dla nas sens z naszych szczególnych powodów.

BsonSerializer.RegisterSerializer(typeof(DateTime), new MyMongoDBDateTimeSerializer());


public class MyMongoDBDateTimeSerializer : DateTimeSerializer
{
    //  MongoDB returns datetime as DateTimeKind.Utc, which cann't be used in our timezone conversion logic
    //  We overwrite it to be DateTimeKind.Unspecified
    public override object Deserialize(MongoDB.Bson.IO.BsonReader bsonReader, System.Type nominalType, MongoDB.Bson.Serialization.IBsonSerializationOptions options)
    {
        var obj = base.Deserialize(bsonReader, nominalType, options);
        var dt = (DateTime) obj;
        return new DateTime(dt.Ticks, DateTimeKind.Unspecified);
    }

    //  MongoDB returns datetime as DateTimeKind.Utc, which cann't be used in our timezone conversion logic
    //  We overwrite it to be DateTimeKind.Unspecified
    public override object Deserialize(MongoDB.Bson.IO.BsonReader bsonReader, Type nominalType, Type actualType, MongoDB.Bson.Serialization.IBsonSerializationOptions options)
    {
        var obj = base.Deserialize(bsonReader, nominalType, actualType, options);
        var dt = (DateTime)obj;
        return new DateTime(dt.Ticks, DateTimeKind.Unspecified);
    }

    //  MongoDB stores all datetime as Utc, any datetime value DateTimeKind is not DateTimeKind.Utc, will be converted to Utc first
    //  We overwrite it to be DateTimeKind.Utc, becasue we want to preserve the raw value
    public override void Serialize(MongoDB.Bson.IO.BsonWriter bsonWriter, System.Type nominalType, object value, MongoDB.Bson.Serialization.IBsonSerializationOptions options)
    {
        var dt = (DateTime) value;
        var utcValue = new DateTime(dt.Ticks, DateTimeKind.Utc);
        base.Serialize(bsonWriter, nominalType, utcValue, options);
    }
}