C# Internal.FieldMetadata类代码示例

		public virtual void InitOnUp(Transaction systemTrans, FieldMetadata fieldMetadata
			)
		{
			ObjectContainerBase anyStream = systemTrans.Container();
			if (!anyStream.MaintainsIndices())
			{
				return;
			}
			if (!fieldMetadata.SupportsIndex())
			{
				Indexed(false);
			}
			TernaryBool indexedFlag = _config.GetAsTernaryBool(IndexedKey);
			if (indexedFlag.DefiniteNo())
			{
				fieldMetadata.DropIndex((LocalTransaction)systemTrans);
				return;
			}
			if (UseExistingIndex(systemTrans, fieldMetadata))
			{
				return;
			}
			if (!indexedFlag.DefiniteYes())
			{
				return;
			}
			fieldMetadata.CreateIndex();
		}

			protected override void Process(FieldMetadata field)
			{
				if (!field.IsVirtual() && field.HasIndex())
				{
					this._enclosing.ProcessBTree(context, field.GetIndex(context.SystemTrans()));
				}
			}

		public QField(Transaction a_trans, string name, FieldMetadata fieldMetadata, int 
			classMetadataID, int a_index)
		{
			// C/S only	
			i_trans = a_trans;
			i_name = name;
			_fieldMetadata = fieldMetadata;
			i_classMetadataID = classMetadataID;
			_fieldHandle = a_index;
			if (_fieldMetadata != null)
			{
				if (!_fieldMetadata.Alive())
				{
					_fieldMetadata = null;
				}
			}
		}

			protected override void Process(FieldMetadata field)
			{
				Assert.IsNotNull(expectedNames.Remove(field.GetName()));
			}

		public FieldIndexException(string msg, Exception cause, FieldMetadata field) : this
			(msg, cause, field.ContainingClass().GetName(), field.GetName())
		{
		}

			public FieldValueKey(int id, FieldMetadata field)
			{
				_id = id;
				_field = field;
			}

 public StoredFieldImpl(Transaction transaction, FieldMetadata
     fieldMetadata)
 {
     _transaction = transaction;
     _fieldMetadata = fieldMetadata;
 }

		internal virtual bool Attach(QQuery query, string a_field)
		{
			Db4objects.Db4o.Internal.Query.Processor.QCon qcon = this;
			ClassMetadata yc = GetYapClass();
			bool[] foundField = new bool[] { false };
			ForEachChildField(a_field, new _IVisitor4_101(foundField, query));
			if (foundField[0])
			{
				return true;
			}
			QField qf = null;
			if (yc == null || yc.HoldsAnyClass())
			{
				int[] count = new int[] { 0 };
				FieldMetadata[] yfs = new FieldMetadata[] { null };
				i_trans.Container().ClassCollection().AttachQueryNode(a_field, new _IVisitor4_119
					(yfs, count));
				if (count[0] == 0)
				{
					return false;
				}
				if (count[0] == 1)
				{
					qf = yfs[0].QField(i_trans);
				}
				else
				{
					qf = new QField(i_trans, a_field, null, 0, 0);
				}
			}
			else
			{
				if (yc.IsTranslated())
				{
					i_trans.Container()._handlers.DiagnosticProcessor().DescendIntoTranslator(yc, a_field
						);
				}
				FieldMetadata yf = yc.FieldMetadataForName(a_field);
				if (yf != null)
				{
					qf = yf.QField(i_trans);
				}
				if (qf == null)
				{
					qf = new QField(i_trans, a_field, null, 0, 0);
				}
			}
			QConPath qcp = new QConPath(i_trans, qcon, qf);
			query.AddConstraint(qcp);
			qcon.AddConstraint(qcp);
			return true;
		}

		private bool HasBTreeIndex(FieldMetadata field)
		{
			return !field.IsVirtual();
		}

		public virtual void AddIndexEntry(FieldMetadata fieldMetadata, object obj)
		{
			if (!_currentBuffer.HasParent())
			{
				object indexEntry = (obj == _currentMarshalledObject) ? _currentIndexEntry : obj;
				if (_isNew || !UpdateDepth().CanSkip(_reference))
				{
					fieldMetadata.AddIndexEntry(Transaction(), ObjectID(), indexEntry);
				}
				return;
			}
			_currentBuffer.RequestIndexEntry(fieldMetadata);
		}

			protected override void Process(FieldMetadata field)
			{
				if (field.CanAddToQuery(fieldName))
				{
					foundField.value = field;
				}
			}

		internal virtual void Unmarshall(Transaction a_trans)
		{
			if (i_classMetadataID != 0)
			{
				ClassMetadata yc = a_trans.Container().ClassMetadataForID(i_classMetadataID);
				_fieldMetadata = (FieldMetadata)yc._aspects[_fieldHandle];
			}
		}

		private bool CollectReflectFields(Collection4 collectedAspects)
		{
			bool dirty = false;
			IReflectField[] reflectFieldArray = ReflectFields();
			for (int reflectFieldIndex = 0; reflectFieldIndex < reflectFieldArray.Length; ++reflectFieldIndex)
			{
				IReflectField reflectField = reflectFieldArray[reflectFieldIndex];
				if (!StoreField(reflectField))
				{
					continue;
				}
				Db4objects.Db4o.Internal.ClassMetadata classMetadata = Handlers4.ErasedFieldType(
					Container(), reflectField.GetFieldType());
				if (classMetadata == null)
				{
					continue;
				}
				FieldMetadata field = new FieldMetadata(this, reflectField, classMetadata);
				if (Contains(collectedAspects, field))
				{
					continue;
				}
				dirty = true;
				collectedAspects.Add(field);
			}
			return dirty;
		}

		private object ReadFieldValue(int id, FieldMetadata field)
		{
			ByteArrayBuffer buffer = BufferFor(id);
			HandlerVersion handlerVersion = field.ContainingClass().SeekToField(_transaction, 
				buffer, field);
			if (handlerVersion == HandlerVersion.Invalid)
			{
				return null;
			}
			QueryingReadContext context = new QueryingReadContext(_transaction, handlerVersion
				._number, buffer, id);
			return field.Read(context);
		}

		private object GetFieldValue(int id, FieldMetadata field)
		{
			SodaQueryComparator.FieldValueKey key = new SodaQueryComparator.FieldValueKey(id, 
				field);
			object cachedValue = _fieldValueCache[key];
			if (null != cachedValue)
			{
				return cachedValue;
			}
			object fieldValue = ReadFieldValue(id, field);
			_fieldValueCache[key] = fieldValue;
			return fieldValue;
		}