using DataViews to jump to a sorted set of records without scanning the whole view

[J. C. Clay]

I've created a DataView in C#.

I've also sorted my records on product_name.

If I return 6000 products and want to get to products
(3000-3020) I wrote the following code:

WriteView(myView,3000,3020)

public void WriteView(DataView myView,int startIdx,int endIdx)
{
int n;
n=0;
myView.Sort="product_name";

foreach (DataRowView myDRV in myView)

{
n=n+1;
for (int i = 0; i < myView.Table.Columns.Count; i++)
{
if ((n > startIdx) && (n < endIdx))
{
Console.Write(myDRV[i] + "\t");
Console.WriteLine("");
}
}
}

When I run this it works but I wonder if I can get the same result
without having to scan through the DataView.

I've tried skipping over the first 3000 records using the command
Console.WriteLine(myView.Table.Rows[j][i]);

where j=3000 to 3020 but this does not return the sorted order; it
returns the DataView in the intial sequence that it was first fetched
from the dbase.

Does anyone have any other suggestions.

Thanks

J.C. Klay

[Nicholas Paldino [.NET/C# MVP]]

J. C. Clay,

If the index is stored in the data set itself in a column, then you can
set the RowFilter property to the following and it should work:

// Set the filter to only include items in the index range.
myView.RowFilter = String.Format("<fieldname> > {0} and <fieldname> < {1}",
startIdx, endIdx);

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- ni**************@exisconsulting.com

"J. C. Clay" <bi********@yahoo.com> wrote in message
news:30**************************@posting.google.c om...

I've created a DataView in C#.

I've also sorted my records on product_name.

If I return 6000 products and want to get to products
(3000-3020) I wrote the following code:

WriteView(myView,3000,3020)

public void WriteView(DataView myView,int startIdx,int endIdx)
{
int n;
n=0;
myView.Sort="product_name";

foreach (DataRowView myDRV in myView)

{
n=n+1;
for (int i = 0; i < myView.Table.Columns.Count; i++)
{
if ((n > startIdx) && (n < endIdx))
{
Console.Write(myDRV[i] + "\t");
Console.WriteLine("");
}
}
}

When I run this it works but I wonder if I can get the same result
without having to scan through the DataView.

I've tried skipping over the first 3000 records using the command
Console.WriteLine(myView.Table.Rows[j][i]);

where j=3000 to 3020 but this does not return the sorted order; it
returns the DataView in the intial sequence that it was first fetched
from the dbase.

Does anyone have any other suggestions.

Thanks

J.C. Klay