dataview problem

  • Thread starter Thread starter av
  • Start date Start date
A

av

Hi,

I'm at a loss on this one. I have a generic method for returning
lookupdata in a datatable X with 2 columns (ID, DESC). The X has a
X.DefaultView.Sort = "DESC". I add rows from the table to a combo by
cycling through the defaultview - so I can get them in sort order. My
problem is that the defaultview is returning a count of zero even
though there are rows in the table. If I then set the sort order to
blank, then suddenly the defaultview.Count = X.rows.count.

The really weird thing is that this code has worked for ages with no
changes. I havent' installed any new framework software and the code
hasn't changed at all. Has anyone experienced this? Would appreciate
any help

regards

avner
 
Hi Dear avner (av),

If I understand your problem correctly (correct me if am wrong)

You are working on winforms(ie. windows forms application)

x is your DataTabel

you want to use X.DefaultView.Sort

and populate the combo box. right.

X.DefaultView.Sort="Field Name" which you fetch from database and populate
the DataSet and inturn DataTable.

you are also right in sorting if "DESC" is your Description but not
Descending like in the SQL Queries

After making X.DefaultView.Sort="DESC", If you populate the DataGrid control
in the winfoms, you can see the sorting as per "DESC"

But in Combobox it will not reflect. as well you can use the sort() Method
of the combo box itself.

look up my code , i did not face any problem

after filling the dataset like

da.Fill(ds, "FIRST_TABLE")

Me.ComboBox1.Items.Clear()

Dim dt As DataTable = ds.Tables("FIRST_TABLE")

'Instead of your "DESC" , I have given "Name"

dt.DefaultView.Sort = "Name"

Dim oRow As DataRow
For Each oRow In dt.Rows
Me.ComboBox1.Items.Add(oRow("Name"))
Next

If you want to see the sorting in combo box

ComboBox1.Sorted = True

Now check with the combo box, all the items will be sorted.

But If you want to see the sorting of the DataTable in your case "X"
After doing the sorting for example;

dt.DefaultView.Sort = "Name"


'Populate the DataGrid control

Me.DataGrid1.DataSource = dt

now you can see the sorting of the dt.DefaultView.Sort = "Name", in your case

X.DefaultView.Sort

I hope, I have made it clear.

For anything and everything get back to me

bye
Venkat_KL
 
Hi Venat,

thanks for your reply. I know that sorting can be set on each combo
box, but I do it in one place as a matter of convenience. Your reply
has higlighted something I never picked up in my code, which is that my
column name 'DESC' also happens to be the keyword to sort descending -
not my intention at all!

My problem is that the dataview is not functioning as I expect. As I
mentioned before the count of the dataview is always zero even though
there is no rowfilter. Only the sort propery is set. I have now changed
it as follows "[DESC] ASC" to sort ascending on the DESC column. In the
context of my application I still get the same problem after loading my
table. But if I try it in a separate application it seems to work ok.
Also the same app on different machines doesn't exprience this problem
- go figure.

It's one of those issues I'm going to have to struggle through to find
out what's going on.

thanks,

Avner
 
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