private static InternalEntityEntry?TryPropagateValue(InternalEntityEntry entry, IProperty property, IProperty?generationProperty)
{
var entityType = entry.EntityType;
var stateManager = entry.StateManager;
foreach (var foreignKey in entityType.GetForeignKeys())
{
for (var propertyIndex = 0; propertyIndex < foreignKey.Properties.Count; propertyIndex++)
{
if (property == foreignKey.Properties[propertyIndex])
{
var principal = foreignKey.DependentToPrincipal == null
? null
: entry[foreignKey.DependentToPrincipal];
InternalEntityEntry?principalEntry = null;
if (principal != null)
{
principalEntry = stateManager.GetOrCreateEntry(principal, foreignKey.PrincipalEntityType);
}
else if (foreignKey.PrincipalToDependent != null)
{
foreach (var danglerEntry in stateManager.GetRecordedReferrers(entry.Entity, clear: false))
{
if (danglerEntry.Item1 == foreignKey.PrincipalToDependent)
{
principalEntry = danglerEntry.Item2;
break;
}
}
}
if (principalEntry != null)
{
var principalProperty = foreignKey.PrincipalKey.Properties[propertyIndex];
if (principalProperty != property)
{
var principalValue = principalEntry[principalProperty];
if (generationProperty == null ||
!principalProperty.ClrType.IsDefaultValue(principalValue))
{
entry.PropagateValue(principalEntry, principalProperty, property);
return(principalEntry);
}
}
}
break;
}
}
}
return(null);
}