Question

I’ve got 2 object arrays that Im getting from the DB, some overlap, so I have to make a distinct func.

I tried to make a lambda expression , but I still got an overlapped objects.

this is my code:

ArtObject[] pinui = new ArtObject[root.Count - 1];
ArtObject[] c1=     new ArtObject[root2.Count - 1];

pinui = getArticlesArray(root2, pinui);
c1= getArticlesArray(root, c1);

art = new ArtObject[c1.Count()+pinui.Count()];

pinui.CopyTo(art, 0);
c1.CopyTo(art, pinui.Count());

art = art.Distinct().OrderByDescending(a => a.dateTosort).ToArray();

I guess something wrong with my last line, art = art.Distinct().OrderByDescending(a => a.dateTosort).ToArray(); .. I wonder what and how can I get only the distinct objects..?

Answer 1

If you do distinct on one of fields, you can use GroupBy then get First:

pinui.Concat(c1).GroupBy(a => a.Description, (key, g) => g.First())
    .OrderByDescending(a => a.dateTosort).ToArray();