Karl,
Thank you so much! That works very well - excellently in fact! This
technique might prove for a couple of other pages in the site aswell. Thanks
again!
Haydn
"Karl" <none> wrote in message
news:%...
> Without knowing more, I would retrieve all records into a DataTable and
> cache the datatable in the HttpRuntime.Cache object. I would use the
> querystring to pass the index of the datatable to get. Something like
(not
> actually code as I'm writting it without my trusty editor, but enough to
get
> you started)
>
>
> Page_Load
> Dim imageIndex as integer
> if Request.QueryString("index") is nothing then
> imageIndex = 0
> else
> imageIndex = Request.Querystring("index")
> end if
>
> Dim table as DataTable = GetImages()
> if imageIndex >= table.rows.Count then
> imageIndex = 0
> end if
>
> DataRow dr = table.rows[imageIndex]
> 'do something with the datarow
> End
>
> Function GetImages() as DataTable
> Dim cacheKey as string = "AllImages"
> DataTable dt = ctype(cache(cacheKey), datatable)
> if dt is nothing then
> Dim Conn as new SqlConnect("...")
> dim cmd as new SqlCommand("command here", conn)
> dim da as new DataAdapter(cmd)
> dt = new DataTable
> da.fill(dt)
> 'close and dispose your stuff
> Cache.Insert(cacheKey, dt, nothing, DateTime.Now.AddHours(1),
> TimeSpan.Zero)
> end if
> return dt
> End
>
> You can then pass Index=(imageIndex+1) to get the next image and
> Index=(imageIndex-1) to get the previous one. Hope that helps.
>
> Karl
>
>
> "Haydnw" <> wrote in message
> news:%...
> > Hi Karl, thanks for the reply. I'm fairly new to .NET in general, so
it's
> > likely there is a better way! Basically I have a database containing
info
> > about lots of different images, including the filename. The images are
> > viewed one at a time, on a page with 'Next' and 'Previous' buttons.
> > Obviously, the 'Next' button takes you to the next image in the
database.
> > However, file names are numeric but not sequential so the current file
> name
> > has no relation to whatever comes next! So if I'm viewing an image with
> > filename 00003, I have no idea what the next one is.
> >
> > Basically what I need is a way to return a set of results from access,
and
> > say 'Get the SECOND row this time' or 'Get the THIRD row this time'. I
> don't
> > know any way of doing this. I thought that by dumping them in an array,
I
> > would be able to reference the values in the array in a more structured
> > fashion because I know they are sequential starting from 0.
> >
> > One alternative is to modify my SQL to get the top record where the
> filename
> > is greater than the one currently being viewed (if 'Next' button
clicked)
> or
> > less than the one currently being viewed (if 'Previous' button clicked).
I
> > realised this after my original post and it's now looking favourite! But
I
> > thought another advantage of the array method might be that once I've
> > queried the database once to get all the info, I can maintain it through
> > page postbacks rather than querying the database for one record each
time
> > the page is loaded. What are your views on this? Would the overheads of
> > maintaining a large two-dimensional array be greater than querying the
> > database each time the page loads?
> >
> > Thank you very much,
> > Haydn
> >
> >
> >
> > "Karl" <none> wrote in message
> news:...
> > > Haydn,
> > > I'd love to know why you want to do this there is likely a better
> > > alternative for whatever it is you are trying to do.
> > >
> > > The only way I know how to do what you want to do is to manually loop
> > > through your datasource:
> > >
> > > DataTable dt = new DataTable();
> > > dt.Columns.Add("column1");
> > > dt.Columns.Add("column2");
> > > dt.Columns.Add("column3");
> > > for (int i = 0; i < 5; i++){
> > > DataRow dr = dt.NewRow();
> > > dr[0] = 1 * (i + 1);
> > > dr[1] = 3 * (i + 1);
> > > dr[2] = 2 * (i + 1);
> > > dt.Rows.Add(dr);
> > > }
> > > int[,] array = new int[dt.Columns.Count,dt.Rows.Count];
> > > for (int i = 0; i < dt.Rows.Count; i++){
> > > for (int j = 0; j < dt.Columns.Count; j++){
> > > array[j,i] = Convert.ToInt32(dt.Rows[i][j]);
> > > }
> > > }
> > >
> > > Karl
> > >
> > > "Haydnw" <> wrote in message
> > > news:...
> > > > Hi,
> > > >
> > > > I'd like to put a load of database results (several rows for 5
fields)
> > > into
> > > > a two-dimensional array. Now, this may be a really stupid question,
> but
> > > can
> > > > someone give me a pointer for how to do it? I can bind data to
> datagrids
> > > and
> > > > lists and stuff all day long, but can't seem to grasp this one. Any
> > > pointers
> > > > to a useful article / demo (or just any useful pointers!) would be
> much
> > > > appreciated.
> > > >
> > > > Thanks,
> > > > Haydn
> > > >
> > > >
> > >
> > >
> >
> >
>
>
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