Datalist/datatable sorting

[Brian Barnes]

Hi,
I know this has been done quite often before, but all my research and trials
have not worked. Basically I am trying to display a sorted list of e-mail
Addresses in a datalist control (using web forms) from a dataset. The only
table in the dataset has 2 columns (UserID (Guid (defined as a string),
primary Key) and UserEmail (string)) and is filled from an Access database.

It is not practical to bring the data in sorted (although it is possible) as
it makes the SQL statement "hairy" (and I like to write clean code). Also I
doubt the speed gain (if any) will be negligible due to the small size I
expect the table to be.

My current code is:

datGroupAdmin.t blUser.DefaultV iew.Sort = "UserEmail"
lstGroupAdmin.D ataSource = datGroupAdmin.t blUser
lstGroupAdmin.D ataBind()

and does not show the list sorted.

I also have tried:
datGroupAdmin.t blUser.DefaultV iew.Sort = "UserEmail"
lstGroupAdmin.D ataSource = datGroupAdmin.t blUser.DefaultV iew
lstGroupAdmin.D ataBind()

again to no avail.

I have also tried implementing my own sort method:
tblClone = tblTest.Copy
tblTest.Clear()

While tblClone.Rows.C ount > 0
rowLow = tblClone.Rows(0 )
For Each row In tblClone.Rows
If row.Item(0).ToS tring.ToLower < rowLow.Item(0). ToString.ToLowe r
Then
RowLow = row
End If
Next
tblTest.Rows.Ad d(rowLow)
tblClone.Rows.R emove(row)
End While

but this came up with a runtime error "5" "This row already belongs to
another table" (I realise that this isn't the best sort method, it was a
test to see if I could get it to work).

At one stage, I believe I had the datatable sorted (but this did not display
sorted in the datalist - I'm sure I don't re-initialise the datatable or
datalist elsewhere).

--
Brian Barnes

[Cor Ligthert]

Brian,

I tested your problem. The code beneath gave me a datalist what looks like
this.

1 Em*********@wat hever.com
2 Em*********@wat hever.com
\\\
Dim dt As New DataTable
dt.Columns.Add( "Id")
dt.Columns.Add( "EmailAdres ")
dt.Rows.Add(dt. NewRow)
dt.Rows.Add(dt. NewRow)
dt.Rows(0)(0) = "2"
dt.Rows(1)(0) = "1"
dt.Rows(0)(1) = "Em*********@wa thever.com"
dt.Rows(1)(1) = "Em*********@wa thever.com"
dt.DefaultView. Sort = "Id"
dataList1.DataS ource = dt.DefaultView
dataList1.DataB ind()
///

I hope this helps?

Cor

[Brian Barnes]

"Cor Ligthert" <no************ @planet.nl> wrote in message
news:ON******** ********@tk2msf tngp13.phx.gbl. ..

Brian,

I tested your problem. The code beneath gave me a datalist what looks like
this.

1 Em*********@wat hever.com
2 Em*********@wat hever.com
\\\
Dim dt As New DataTable
dt.Columns.Add( "Id")
dt.Columns.Add( "EmailAdres ")
dt.Rows.Add(dt. NewRow)
dt.Rows.Add(dt. NewRow)
dt.Rows(0)(0) = "2"
dt.Rows(1)(0) = "1"
dt.Rows(0)(1) = "Em*********@wa thever.com"
dt.Rows(1)(1) = "Em*********@wa thever.com"
dt.DefaultView. Sort = "Id"
dataList1.DataS ource = dt.DefaultView
dataList1.DataB ind()
///

I hope this helps?

Unfortunately I had tried this (and listed this in my orignal post). It
wasn't sorting it by guid either. It did put me on the right track though.

On further inspection, I found that the default view was indeed sorted, and
that I had fields in the properties box in the form designer. I deleted
these (so now there were no databound variables set in the form designer)
and set the DataTextField & DataValue field in code. The final code (that
works!) is:

datGroupAdmin.t blUser.DefaultV iew.Sort = "UserEmail"
lstGroupAdmin.D ataSource = datGroupAdmin.t blUser.DefaultV iew
lstGroupAdmin.D ataValueField = "UserId"
lstGroupAdmin.D ataTextField = "UserEmail"
lstGroupAdmin.D ataBind()

All the more reason not to trust Microsoft's form designer. It is possible
to build web forms without it, but some of the code required to do this is
tedious (try building a html table in code ;-) - yes I have done it as part
of a page template).

--
Brian Barnes
Now to apply that code to all the other datalists :-(

[Cor Ligthert]

Brian,

dt.DefaultView. Sort = "Id"
dataList1.DataS ource = dt.DefaultView
dataList1.DataB ind()

Unfortunately I had tried this (and listed this in my orignal post). It
wasn't sorting it by guid either. It did put me on the right track though.
I tested it, so that is strange that you did not saw that.

datGroupAdmin.t blUser.DefaultV iew.Sort = "UserEmail"
lstGroupAdmin.D ataSource = datGroupAdmin.t blUser.DefaultV iew
lstGroupAdmin.D ataValueField = "UserId"
lstGroupAdmin.D ataTextField = "UserEmail"
lstGroupAdmin.D ataBind()

This is the same code I showed you? The only difference is that I have the
DataValueField and DataTextField in the HTML part because I was not using
the designer to get the dataset.

Cor