从覆盖的SaveChanges()更新属性

我需要重写SaveChanges()，以便在某些实体被修改时更新列(NewClub.LastActivityDate)。问题是，很多时候具有LastActivityDate的表(NewClub)不在呈现给SaveChanges()的实体集中，因此我需要一种方法来更新NewClub。LastActivityDate是否在实体集中

这是我到目前为止写的。

Thanks for looking

public override int SaveChanges()
        {
            var saveSuccess = false;
            var newClubPrimaryKeyId = 0;
            ObjectContext ctx = ((IObjectContextAdapter)this).ObjectContext;
            List<ObjectStateEntry> objectStateEntryList =
           ctx.ObjectStateManager.GetObjectStateEntries(EntityState.Added
                                                      | EntityState.Unchanged // need this to get to NewClub when it's not the table being updated
                                                      | EntityState.Modified
                                                      | EntityState.Deleted).ToList();
            foreach (ObjectStateEntry entry in objectStateEntryList)
            {
                //Skip over relationships
                if (entry.IsRelationship) continue;
                //Make sure the entity is a member of the NCO schema: NewClub[...]
                if (SecurityHelper.IsValidNewClubTableName(entry.EntitySet.Name))
                {
                    entityInfoStr += "Entity Name: " + entry.EntitySet.Name + " Entity State: " + entry.State;
                    var nc = entry.Entity as NewClub;
                    var ncp = entry.Entity as NewClubProspect;
                    if (nc != null) { newClubPrimaryKeyId = nc.Id; }
                    else if (ncp != null){newClubPrimaryKeyId = ncp.NewClubId;}
                    //... More comparisons here....

                   //---------------------------------------------------------------
                   //Update NewClub.LastActivityDate where Id == newClubPrimaryKeyId
                   //----------------------------------------------------------------
                    //This does not work
                     string q = @"UPDATE NewClub SET LastActivityDate=" + DateTime.Now + " WHERE Id=" +
                           newClubPrimaryKeyId;
                      var t = ctx.CreateQuery<NewClub>(q);
                }
            }
            try
            {
                 saveSuccess = base.SaveChanges() > 0;
            }
            catch (Exception e)
            {
                string ex = e.ToString();

            }
            return saveSuccess ? 1 : 0; 
        }   

foreach( var entry in objectStateEntryList)
{
    var lastTime = entry.Property("LastActivityDate");
    if(lastTime != null)
    {
        lastTime.CurrentValue = DateTime.Now;
        lastTime.IsModified = true; // be careful with this, throws exception if object is added not modified
    }
}