Several Questions on ADO.NET

[cnSoftware]

Hi,there

I get some problems when I am struggling
in ADO.NET programming. I should really preciate
your kindly advice.

1.How could I perform a data paging on master-detail
datasets,especially the detail one? As I thought,
I retrieve the master data and detail data seperately
and then associate them through dataRelation.
So it seems that I can paging the master data readily
but how about the detail data?

2.Suppose I use DataSet only in my asp.net application.
How could I re-position to the row after I insert a
new row into the dataset?

3.I am editing a datarow. When I modify the value in a column,
I hope value in another column should change correspondingly ASAP.
For instance, the "Cost" column should change with "Price"
column and "Quantity" column correspondingly. In what event
should I place the code?

Thanks.

 

[Sahil Malik]

1. ASP.NET or Winforms?
2. By saving the last row # and going back to
InterestedTable.DataRowCollection[thatnumber]. Dataset unlike Recordset
allows for free up and down traversal on the dataset, like RAM
3. Use DataColumn.Expression. If you insist on doing this using events, then
in 1.1 ur gonna have to use events on either the table or a default dataview
associated with the table. in .NET 2.0 you've got a lot of brand new events
for this purpose. (See
http://dotnetjunkies.com/WebLog/sahilmalik/posts/37433.aspx ).

- Sahil Malik
http://dotnetjunkies.com/weblog/sahilmalik

 

[Cor Ligthert]

Hi,

In addition to Sahil,

A dataset cannot really be positioned . A dataset holds datatable, which
holds rows which can be positioned.

A datatable can be used via a dataview (or the standard defaultview) which
makes it possible to select a part of the rows or see them in another sorted
way.

Just meant as addition.

Cor