Question

I have a problem regarding duplicate record.I have a table called tbl_Kisiler as shown below.

 ID     Adi
 ---   ----
 1     harun
 2     ahmet
 3     melis
 2     ali 

I have a ListBox like upper table.My question is:I want to move a new inside ListBox those duplicate ID records in C#.How can I do that?

---

ID,      Adi,     
----      ----      
1        harun
3        melis
2        ali

Cheers,

Answer 1

Do you mean you want to create a new listbox containing records with duplicate ids, i.e.

ID    Adi
---  ----
2    harun
2    ali

If that is what you want to do, you can use linq to select the duplicates

var duplicateIDs = from r in records
                   group r by r.id into g
                   where g.Count() > 1
                   select g.Key;

var duplicateRecords = from r in records
                       where duplicateIDs.Contains(r.id)
                       select r;

var nonDuplicateRecords = from r in records
                          where !duplicateIDs.Contains(r.id)
                          select r;

listBox2.DataSource = duplicateRecords.ToList();
listBox1.DataSource = nonDuplicateRecords.ToList();

Apologies if I’ve misunderstood your question. I’m fairly sure the linq queries could be improved, hopefully someone can suggest an more fluent way of doing it.