private void WriteExpandedNavigationProperty( KeyValuePair <IEdmNavigationProperty, SelectExpandClause> navigationPropertyToExpand, EntityInstanceContext entityInstanceContext, ODataWriter writer) { Contract.Assert(entityInstanceContext != null); Contract.Assert(writer != null); IEdmNavigationProperty navigationProperty = navigationPropertyToExpand.Key; SelectExpandClause selectExpandClause = navigationPropertyToExpand.Value; object propertyValue = entityInstanceContext.GetPropertyValue(navigationProperty.Name); if (propertyValue != null) { // create the serializer context for the expanded item. ODataSerializerContext nestedWriteContext = new ODataSerializerContext(entityInstanceContext, selectExpandClause, navigationProperty); // write object. ODataEdmTypeSerializer serializer = SerializerProvider.GetEdmTypeSerializer(navigationProperty.Type); if (serializer == null) { throw new SerializationException( Error.Format(SRResources.TypeCannotBeSerialized, navigationProperty.Type.ToTraceString(), typeof(ODataMediaTypeFormatter).Name)); } serializer.WriteObjectInline(propertyValue, navigationProperty.Type, writer, nestedWriteContext); } }
private void WriteFeed(IEnumerable enumerable, IEdmTypeReference feedType, ODataWriter writer, ODataSerializerContext writeContext) { Contract.Assert(writer != null); Contract.Assert(writeContext != null); Contract.Assert(enumerable != null); Contract.Assert(feedType != null); IEdmEntityTypeReference elementType = GetEntityType(feedType); ODataFeed feed = CreateODataFeed(enumerable, feedType.AsCollection(), writeContext); if (feed == null) { throw new SerializationException(Error.Format(SRResources.CannotSerializerNull, Feed)); } ODataEdmTypeSerializer entrySerializer = SerializerProvider.GetEdmTypeSerializer(elementType); if (entrySerializer == null) { throw new SerializationException( Error.Format(SRResources.TypeCannotBeSerialized, elementType.FullName(), typeof(ODataMediaTypeFormatter).Name)); } // save this for later to support JSON lite streaming. Uri nextPageLink = feed.NextPageLink; feed.NextPageLink = null; writer.WriteStart(feed); foreach (object entry in enumerable) { if (entry == null) { throw new SerializationException(SRResources.NullElementInCollection); } entrySerializer.WriteObjectInline(entry, elementType, writer, writeContext); } // Subtle and suprising behavior: If the NextPageLink property is set before calling WriteStart(feed), // the next page link will be written early in a manner not compatible with streaming=true. Instead, if // the next page link is not set when calling WriteStart(feed) but is instead set later on that feed // object before calling WriteEnd(), the next page link will be written at the end, as required for // streaming=true support. if (nextPageLink != null) { feed.NextPageLink = nextPageLink; } writer.WriteEnd(); }
private void WriteExpandedNavigationProperty( KeyValuePair <IEdmNavigationProperty, SelectExpandClause> navigationPropertyToExpand, EntityInstanceContext entityInstanceContext, ODataWriter writer) { Contract.Assert(entityInstanceContext != null); Contract.Assert(writer != null); IEdmNavigationProperty navigationProperty = navigationPropertyToExpand.Key; SelectExpandClause selectExpandClause = navigationPropertyToExpand.Value; object propertyValue = entityInstanceContext.GetPropertyValue(navigationProperty.Name); if (propertyValue == null) { if (navigationProperty.Type.IsCollection()) { // A navigation property whose Type attribute specifies a collection, the collection always exists, // it may just be empty. // If a collection of entities can be related, it is represented as a JSON array. An empty // collection of entities (one that contains no entities) is represented as an empty JSON array. writer.WriteStart(new ODataFeed()); } else { // If at most one entity can be related, the value is null if no entity is currently related. writer.WriteStart(entry: null); } writer.WriteEnd(); } else { // create the serializer context for the expanded item. ODataSerializerContext nestedWriteContext = new ODataSerializerContext(entityInstanceContext, selectExpandClause, navigationProperty); // write object. ODataEdmTypeSerializer serializer = SerializerProvider.GetEdmTypeSerializer(navigationProperty.Type); if (serializer == null) { throw new SerializationException( Error.Format(SRResources.TypeCannotBeSerialized, navigationProperty.Type.ToTraceString(), typeof(ODataMediaTypeFormatter).Name)); } serializer.WriteObjectInline(propertyValue, navigationProperty.Type, writer, nestedWriteContext); } }