private static object CreateFullUpdateInstance(DataModificationItem entry, Type entityType)
{
// The algorithm for a "FullReplaceUpdate" is taken from ObjectContextServiceProvider.ResetResource
// in WCF DS, and works as follows:
// - Create a new, blank instance of the entity.
// - Copy over the key values and set any updated values from the client on the new instance.
// - Then apply all the properties of the new instance to the instance to be updated.
// This will set any unspecified properties to their default value.
object newInstance = Activator.CreateInstance(entityType);
ChangeSetInitializer.SetValues(newInstance, entityType, entry.EntityKey);
ChangeSetInitializer.SetValues(newInstance, entityType, entry.LocalValues);
return(newInstance);
}
private static async Task PrepareEntry <TEntity>(
SubmitContext context,
DbContext dbContext,
DataModificationItem entry,
DbSet <TEntity> set,
CancellationToken cancellationToken) where TEntity : class
{
Type entityType = typeof(TEntity);
TEntity entity;
if (entry.DataModificationItemAction == DataModificationItemAction.Insert)
{
// TODO: See if Create method is in DbSet<> in future EF7 releases, as the one EF6 has.
entity = (TEntity)Activator.CreateInstance(typeof(TEntity));
ChangeSetInitializer.SetValues(entity, entityType, entry.LocalValues);
set.Add(entity);
}
else if (entry.DataModificationItemAction == DataModificationItemAction.Remove)
{
entity = (TEntity)await ChangeSetInitializer.FindEntity(context, entry, cancellationToken);
set.Remove(entity);
}
else if (entry.DataModificationItemAction == DataModificationItemAction.Update)
{
if (entry.IsFullReplaceUpdateRequest)
{
entity = (TEntity)ChangeSetInitializer.CreateFullUpdateInstance(entry, entityType);
dbContext.Update(entity);
}
else
{
entity = (TEntity)await ChangeSetInitializer.FindEntity(context, entry, cancellationToken);
var dbEntry = dbContext.Attach(entity);
ChangeSetInitializer.SetValues(dbEntry, entry);
}
}
else
{
throw new NotSupportedException(Resources.DataModificationMustBeCUD);
}
entry.Entity = entity;
}