/// <summary>
/// Recursively enable or disable tracking on trackable entities in an object graph.
/// </summary>
/// <param name="item">Trackable object</param>
/// <param name="enableTracking">Enable or disable change-tracking</param>
/// <param name="visitationHelper">Circular reference checking helper</param>
/// <param name="oneToManyOnly">True if tracking should be set only for OneToMany relations</param>
public static void SetTracking(this ITrackable item, bool enableTracking,
ObjectVisitationHelper visitationHelper = null, bool oneToManyOnly = false)
{
// Iterator entity properties
foreach (var navProp in item.GetNavigationProperties())
{
// Skip if 1-M only
if (!oneToManyOnly)
{
// Set tracking on 1-1 and M-1 properties
foreach (var refProp in navProp.AsReferenceProperty())
{
// Get ref prop change tracker
ITrackingCollection refChangeTracker = item.GetRefPropertyChangeTracker(refProp.Property.Name);
if (refChangeTracker != null)
{
// Set tracking on ref prop change tracker
refChangeTracker.SetTracking(enableTracking, visitationHelper, oneToManyOnly);
}
}
}
// Set tracking on 1-M and M-M properties (if not 1-M only)
foreach (var colProp in navProp.AsCollectionProperty <ITrackingCollection>())
{
bool isOneToMany = !IsManyToManyChildCollection(colProp.EntityCollection);
if (!oneToManyOnly || isOneToMany)
{
colProp.EntityCollection.SetTracking(enableTracking, visitationHelper, oneToManyOnly);
}
}
}
}
/// <summary>
/// Recursively enable or disable tracking on trackable entities in an object graph.
/// </summary>
/// <param name="item">Trackable object</param>
/// <param name="enableTracking">Enable or disable change-tracking</param>
/// <param name="visitationHelper">Circular reference checking helper</param>
public static void SetTracking(this ITrackable item,
bool enableTracking, ObjectVisitationHelper visitationHelper = null)
{
// Iterator entity properties
foreach (var navProp in item.GetNavigationProperties())
{
// Set tracking on 1-1 and M-1 properties
foreach (var refProp in navProp.AsReferenceProperty())
{
// Get ref prop change tracker
ITrackingCollection refChangeTracker = item.GetRefPropertyChangeTracker(refProp.Property.Name);
if (refChangeTracker != null)
{
// Set tracking on ref prop change tracker
refChangeTracker.SetTracking(enableTracking, visitationHelper);
}
}
// Set tracking on 1-M and M-M properties
foreach (var colProp in navProp.AsCollectionProperty <ITrackingCollection>())
{
colProp.EntityCollection.SetTracking(enableTracking, visitationHelper);
}
}
}
/// <summary>
/// Get entities that have been added, modified or deleted, including trackable
/// reference and child entities.
/// </summary>
/// <param name="items">Collection of ITrackable objects</param>
/// <returns>Collection containing only added, modified or deleted entities</returns>
private IEnumerable <ITrackable> GetChanges(IEnumerable <ITrackable> items)
{
// Prevent endless recursion by collection
if (!visitationHelper.TryVisit(items))
{
yield break;
}
// Prevent endless recursion by item
items = items.Where(i => visitationHelper.TryVisit(i)).ToList();
// Iterate items in change-tracking collection
foreach (ITrackable item in items)
{
// Downstream changes flag
bool hasDownstreamChanges = false;
// Iterate entity properties
foreach (var navProp in item.GetNavigationProperties())
{
// Process 1-1 and M-1 properties
foreach (var refProp in navProp.AsReferenceProperty())
{
ITrackable trackableRef = refProp.EntityReference;
// if already visited and unchanged, set to null
if (visitationHelper.IsVisited(trackableRef))
{
if ((trackableRef.TrackingState == TrackingState.Unchanged ||
trackableRef.TrackingState == TrackingState.Deleted))
{
EntityInfo(item).RefNavPropUnchanged.Add(refProp.Property);
}
continue;
}
// Get changed ref prop
ITrackingCollection refChangeTracker = trackableRef.GetRefPropertyChangeTracker(refProp.Property.Name);//item.GetRefPropertyChangeTracker(refProp.Property.Name);
if (refChangeTracker != null)
{
hasDownstreamChanges = HasDownstreamChanges(refChangeTracker, trackableRef, item, refProp, hasDownstreamChanges);
}
}
// Process 1-M and M-M properties
foreach (var colProp in navProp.AsCollectionProperty <IList>())
{
// Get changes on child collection
var trackingItems = colProp.EntityCollection;
if (trackingItems.Count > 0)
{
// Continue recursion if trackable hasn't been visited
if (!visitationHelper.IsVisited(trackingItems))
{
hasDownstreamChanges = GetChangesOnChildCollection(trackingItems, hasDownstreamChanges, item, colProp);
}
}
}
}
// Return item if it has changes
if (hasDownstreamChanges || item.TrackingState != TrackingState.Unchanged)
{
yield return(item);
}
}
}