Linq: How to load a second table directly?

Question

Hi,

I have 2 tables here: Auction and Article.

1 Auction has 1 Article. 1 Aricle has x Auctions.

Now I load a list of auctions:

            using (APlattformDatabaseDataContext dc = new APlattformDatabaseDataContext())
        {
            List<Auktion> auctionlist = (from a in dc.Auktion
                                         where a.KäuferID == null
                                         select a).ToList();
            return auctionlist;
        }

But when I want to "txtBla.Text = auction[0].Article.Text;" it isn't loaded. The question isn't why (it is logic that it isn't loaded allready and can't be loaded because the DC is closed), but how can I solve this without letting the DC open?

Answer 1

You can do the following:

DataLoadOptions options = new DataLoadOptions();
options.LoadWith<Auktion>(a => a.Article);
dc.LoadOptions = options;

Answer 2

If you want to eager load the associations like that you should use the DataContext.LoadOptions property like so...

using (APlattformDatabaseDataContext dc = new APlattformDatabaseDataContext())
{
    var dlo = new DataLoadOptions();
    options.LoadWith<Auktion>(o => o.Article);
    dc.LoadOptions = dlo;

    List<Auktion> auctionlist = (from a in dc.Auktion
                                 where a.KäuferID == null
                                 select a).ToList();
    return auctionlist;
}

That way your articles will be loaded when your Auktion objects are retrieved from the database.