internal override void VerifyMultiplicityConstraintsForAdd(bool applyConstraints)
{
if (applyConstraints && !this.IsEmpty())
{
throw EntityUtil.CannotAddMoreThanOneEntityToEntityReference(this.RelationshipNavigation.To, this.RelationshipNavigation.RelationshipName);
}
}
internal override void VerifyNavigationPropertyForAdd(IEntityWrapper wrapper)
{
if (this.TargetAccessor.HasProperty)
{
object value = WrappedOwner.GetNavigationPropertyValue(this);
if (!Object.ReferenceEquals(null, value) && !Object.Equals(value, wrapper.Entity))
{
throw EntityUtil.CannotAddMoreThanOneEntityToEntityReference(
this.RelationshipNavigation.To, this.RelationshipNavigation.RelationshipName);
}
}
}
/// <summary>
/// AddToLocalEnd is used by both APIs a) RelatedEnd.Add b) Value property setter.
/// ApplyConstraints is true in case of RelatedEnd.Add because one cannot add entity to ref it its already set
/// however applyConstraints is false in case of Value property setter because value can be set to a new value
/// even if its non null.
/// </summary>
internal override void AddToLocalCache(IEntityWrapper wrappedEntity, bool applyConstraints)
{
if (wrappedEntity != _wrappedCachedValue)
{
TransactionManager tm = ObjectContext != null ? ObjectContext.ObjectStateManager.TransactionManager : null;
if (applyConstraints && null != _wrappedCachedValue.Entity)
{
// The idea here is that we want to throw for constraint violations in things that we are bringing in,
// but not when replacing references of things already in the context. Therefore, if the the thing that
// we're replacing is in ProcessedEntities it means we're bringing it in and we should throw.
if (tm == null || tm.ProcessedEntities == null || tm.ProcessedEntities.Contains(_wrappedCachedValue))
{
throw EntityUtil.CannotAddMoreThanOneEntityToEntityReference(this.RelationshipNavigation.To, this.RelationshipNavigation.RelationshipName);
}
}
if (tm != null && wrappedEntity.Entity != null)
{
// Setting this flag will prevent the FK from being temporarily set to null while changing
// it from one value to the next.
tm.BeginRelatedEndAdd();
}
try
{
ClearCollectionOrRef(null, null, false);
_wrappedCachedValue = wrappedEntity;
_cachedValue = (TEntity)wrappedEntity.Entity;
}
finally
{
if (tm != null && tm.IsRelatedEndAdd)
{
tm.EndRelatedEndAdd();
}
}
}
}