How to resort records in a dataSet?

3 Nov 2007 6:18 PM

Andrew

Hello, friends,

We have an app in c#.net 2003. There is a dataSet. Its data are populated to
a customized list in a loop (NO data binding, now and future). We need to
modify it so that it can be sorted based on user's selections.

I tried the follows by using DataView, but no luck: It still keeps the
original order.

Any ideas? Any other methods that we can resort records in a dataSet? Thanks !

-----------------------

DataView mDataView = new DataView();
mDataView = mDataSet.Tables[0].DefaultView;
mDataView.Sort = "--user's selections--";

mDataSet.Tables.Clear();
mDataSet = null;
DataSet mDataSet2 = new DataSet();
mDataSet2.Tables.Add(mDataView.Table);

foreach (DataRow dr in mDataSet2.Tables[0].Rows)
{
//check the order
}

3 Nov 2007 6:38 PM

William Vaughn

The DataView is the correct path. Let's see your code.

--
____________________________________
William (Bill) Vaughn
Author, Mentor, Consultant, Dad, Grandpa
Microsoft MVP
INETA Speaker
www.betav.com
www.betav.com/blog/billva
Please reply only to the newsgroup so that others can benefit.
This posting is provided "AS IS" with no warranties, and confers no rights.
__________________________________
Visit www.hitchhikerguides.net to get more information on my latest book:
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and Hitchhiker's Guide to SQL Server 2005 Compact Edition (EBook)
-----------------------------------------------------------------------------------------------------------------------

Show quote

"Andrew" <And***@discussions.microsoft.com> wrote in message
news:A315398B-FE8E-41C0-943B-01608EA9F883@microsoft.com...
> Hello, friends,
>
> We have an app in c#.net 2003. There is a dataSet. Its data are populated
> to
> a customized list in a loop (NO data binding, now and future). We need to
> modify it so that it can be sorted based on user's selections.
>
> I tried the follows by using DataView, but no luck: It still keeps the
> original order.
>
> Any ideas? Any other methods that we can resort records in a dataSet?
> Thanks !
>
> -----------------------
>
> DataView mDataView = new DataView();
> mDataView = mDataSet.Tables[0].DefaultView;
> mDataView.Sort = "--user's selections--";
>
> mDataSet.Tables.Clear();
> mDataSet = null;
> DataSet mDataSet2 = new DataSet();
> mDataSet2.Tables.Add(mDataView.Table);
>
> foreach (DataRow dr in mDataSet2.Tables[0].Rows)
> {
> //check the order
> }
>
>
>

5 Nov 2007 6:41 PM

William (Bill) Vaughn

Huh?
            cmd = New SqlCommand("SELECT Author, Year_Born FROM Authors ",
cn)
            cn.Open()
            Dim dr As SqlDataReader
            dr = cmd.ExecuteReader
            Dim dt As New DataTable
            dt.Load(dr)
            Dim dv As New DataView
            dv = dt.DefaultView
            dv.Sort = "Year_Born Desc"
            DataGridView1.DataSource = dv
            cn.Close()

Isn't this what you want?
This does not physically resort the table but why would you want to? This
provides a sorted "view" of the table that can be resorted on any column or
set of columns in either ascending (the default) or descending order.

--
____________________________________
William (Bill) Vaughn
Author, Mentor, Consultant
Microsoft MVP
INETA Speaker
www.betav.com/blog/billva
www.betav.com
Please reply only to the newsgroup so that others can benefit.
This posting is provided "AS IS" with no warranties, and confers no rights.
__________________________________
Visit www.hitchhikerguides.net to get more information on my latest book:
Hitchhiker's Guide to Visual Studio and SQL Server (7th Edition)
and Hitchhiker's Guide to SQL Server 2005 Compact Edition (EBook)
-----------------------------------------------------------------------------------------------------------------------

Show quote

"William Vaughn" <billvaNoSPAM@betav.com> wrote in message
news:uTEa1ikHIHA.1188@TK2MSFTNGP04.phx.gbl...
> The DataView is the correct path. Let's see your code.
>
> --
> ____________________________________
> William (Bill) Vaughn
> Author, Mentor, Consultant, Dad, Grandpa
> Microsoft MVP
> INETA Speaker
> www.betav.com
> www.betav.com/blog/billva
> Please reply only to the newsgroup so that others can benefit.
> This posting is provided "AS IS" with no warranties, and confers no
> rights.
> __________________________________
> Visit www.hitchhikerguides.net to get more information on my latest book:
> Hitchhiker's Guide to Visual Studio and SQL Server (7th Edition)
> and Hitchhiker's Guide to SQL Server 2005 Compact Edition (EBook)
> -----------------------------------------------------------------------------------------------------------------------
>
> "Andrew" <And***@discussions.microsoft.com> wrote in message
> news:A315398B-FE8E-41C0-943B-01608EA9F883@microsoft.com...
>> Hello, friends,
>>
>> We have an app in c#.net 2003. There is a dataSet. Its data are populated
>> to
>> a customized list in a loop (NO data binding, now and future). We need to
>> modify it so that it can be sorted based on user's selections.
>>
>> I tried the follows by using DataView, but no luck: It still keeps the
>> original order.
>>
>> Any ideas? Any other methods that we can resort records in a dataSet?
>> Thanks !
>>
>> -----------------------
>>
>> DataView mDataView = new DataView();
>> mDataView = mDataSet.Tables[0].DefaultView;
>> mDataView.Sort = "--user's selections--";
>>
>> mDataSet.Tables.Clear();
>> mDataSet = null;
>> DataSet mDataSet2 = new DataSet();
>> mDataSet2.Tables.Add(mDataView.Table);
>>
>> foreach (DataRow dr in mDataSet2.Tables[0].Rows)
>> {
>> //check the order
>> }
>>
>>
>>
>

4 Nov 2007 10:35 AM

Cor Ligthert[MVP]

Andrew,

The dataview does not sort the table, it is a filter that shows the datarows
using a datarowview in a sorted order.

Cor

4 Nov 2007 7:32 PM

Andrew

Thanks. Then, is there a way to resort records of a data set? Or, in ADO.net,
one has no way to resort records, (unless to query database with a new Order
By statement)?

Show quote

"Cor Ligthert[MVP]" wrote:

> Andrew,
>
> The dataview does not sort the table, it is a filter that shows the datarows
> using a datarowview in a sorted order.
>
> Cor
>

5 Nov 2007 3:27 AM

TAJ

You would need to re-query or use the view to sort. One way is to serialize
the data to xml, sort, then deserialize. Lots of work when you have a
dataview.

TAJ

Show quote

"Andrew" <And***@discussions.microsoft.com> wrote in message
news:06DD409D-3E93-4300-A874-85B465668CE1@microsoft.com...
> Thanks. Then, is there a way to resort records of a data set? Or, in
> ADO.net,
> one has no way to resort records, (unless to query database with a new
> Order
> By statement)?
>
> "Cor Ligthert[MVP]" wrote:
>
>> Andrew,
>>
>> The dataview does not sort the table, it is a filter that shows the
>> datarows
>> using a datarowview in a sorted order.
>>
>> Cor
>>

5 Nov 2007 5:08 AM

Cor Ligthert[MVP]

You can in Visual Studio versions after 2003 use the overloaded
dataview.totable. Be aware that it creates a new datatable.

http://msdn2.microsoft.com/en-us/library/system.data.dataview.totable.aspx

Cor