// public methods /// <summary> /// Gets the actual type of an object by reading the discriminator from a BsonReader. /// </summary> /// <param name="bsonReader">The reader.</param> /// <param name="nominalType">The nominal type.</param> /// <returns>The actual type.</returns> public Type GetActualType(IBsonReader bsonReader, Type nominalType) { // the BsonReader is sitting at the value whose actual type needs to be found var bsonType = bsonReader.GetCurrentBsonType(); if (bsonType == BsonType.Document) { // ensure KnownTypes of nominalType are registered (so IsTypeDiscriminated returns correct answer) BsonSerializer.EnsureKnownTypesAreRegistered(nominalType); // we can skip looking for a discriminator if nominalType has no discriminated sub types if (BsonSerializer.IsTypeDiscriminated(nominalType)) { var bookmark = bsonReader.GetBookmark(); bsonReader.ReadStartDocument(); var actualType = nominalType; if (bsonReader.FindElement(_elementName)) { var context = BsonDeserializationContext.CreateRoot <BsonValue>(bsonReader); var discriminator = BsonValueSerializer.Instance.Deserialize(context); if (discriminator.IsBsonArray) { discriminator = discriminator.AsBsonArray.Last(); // last item is leaf class discriminator } actualType = BsonSerializer.LookupActualType(nominalType, discriminator); } bsonReader.ReturnToBookmark(bookmark); return(actualType); } } return(nominalType); }
// public methods /// <summary> /// Gets the actual type of an object by reading the discriminator from a BsonReader. /// </summary> /// <param name="bsonReader">The reader.</param> /// <param name="nominalType">The nominal type.</param> /// <returns>The actual type.</returns> public Type GetActualType(BsonReader bsonReader, Type nominalType) { // the BsonReader is sitting at the value whose actual type needs to be found var bsonType = bsonReader.GetCurrentBsonType(); if (bsonReader.State == BsonReaderState.Value) { Type primitiveType = null; switch (bsonType) { case BsonType.Boolean: primitiveType = typeof(bool); break; case BsonType.Binary: var bookmark = bsonReader.GetBookmark(); var binaryData = bsonReader.ReadBinaryData(); var subType = binaryData.SubType; if (subType == BsonBinarySubType.UuidStandard || subType == BsonBinarySubType.UuidLegacy) { primitiveType = typeof(Guid); } bsonReader.ReturnToBookmark(bookmark); break; case BsonType.DateTime: primitiveType = typeof(DateTime); break; case BsonType.Double: primitiveType = typeof(double); break; case BsonType.Int32: primitiveType = typeof(int); break; case BsonType.Int64: primitiveType = typeof(long); break; case BsonType.ObjectId: primitiveType = typeof(ObjectId); break; case BsonType.String: primitiveType = typeof(string); break; } // Type.IsAssignableFrom is extremely expensive, always perform a direct type check before calling Type.IsAssignableFrom if (primitiveType != null && (primitiveType == nominalType || nominalType.IsAssignableFrom(primitiveType))) { return(primitiveType); } } if (bsonType == BsonType.Document) { // ensure KnownTypes of nominalType are registered (so IsTypeDiscriminated returns correct answer) BsonSerializer.EnsureKnownTypesAreRegistered(nominalType); // we can skip looking for a discriminator if nominalType has no discriminated sub types if (BsonSerializer.IsTypeDiscriminated(nominalType)) { var bookmark = bsonReader.GetBookmark(); bsonReader.ReadStartDocument(); var actualType = nominalType; if (bsonReader.FindElement(_elementName)) { var discriminator = (BsonValue)BsonValueSerializer.Instance.Deserialize(bsonReader, typeof(BsonValue), null); if (discriminator.IsBsonArray) { discriminator = discriminator.AsBsonArray.Last(); // last item is leaf class discriminator } actualType = BsonSerializer.LookupActualType(nominalType, discriminator); } bsonReader.ReturnToBookmark(bookmark); return(actualType); } } return(nominalType); }