How Do I add records to a Listbox control ?

  • Thread starter Thread starter Gordon
  • Start date Start date
G

Gordon

Hi;

I am a novice asp.net developer who would like to create
a dataset-table and then use the datatable.select cmd. to
look up a value passed from the web calender control. The
value(s) would then be used to populate a listbox on a
web form. I keep getting an error that says that in the
datatable.SELECT statement i.e. mytable.select("column1 =
= '" & aVariable & "'"), that the column1 can't be found.
I can run this program code in a windows program and it
works fine. What am I missing, code wise, to make the
code run under ASP.net ?

Here is the following code that I tried. It is
called from the date selected event of the web calender
control.

Thanks,

Gordon

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

Public Sub SetUpDataBinding()

Dim datConn As String = "Integrated
Security=SSPI;Initial Catalog=DocsDates;Data Source=
(local)\vsdotnet"
Dim cnDocDates As New SqlConnection(datConn)

Try

Dim cmdGetCases As New SqlCommand
("CMasterSelectCommand", cnDocDates)
Dim daCases As New SqlDataAdapter("SELECT
case_id, lname, case_status from CaseMaster", cnDocDates)
Dim daDocs As New SqlDataAdapter("SELECT
case_id, document_nme, doc_dte_start, " & _
"doc_dte_due, comments from CaseDocs where
case_id in " & _
"(SELECT case_id from CaseMaster)",
cnDocDates)
Dim ds As New DataSet
daDocs.Fill(dsCases, "tblCaseDocs")
Session("dsCases") = dsCases

holdDte = Today


Catch ex As System.Data.SqlClient.SqlException

If
HttpContext.Current.Request.UserHostAddress = "129.0.0.5"
Then
Session("CurrentError") = ex.Message
Else
Session("CurrentError") = "Error
processing page."
End If
Server.Transfer("ApplicationError.aspx")
Finally
' cnDocDates.Close()
End Try

End Sub


Public Sub ListBoxFill() ((( This called when a date
is selected on the calendar web control )))))

Dim myCol As DataColumn
Dim myRow As DataRow
Dim currRows() As DataRow


Dim nRow As DataRow()
Dim irow As DataRow

nRow = tblCaseDocs.Select("doc_dte_due = '" &
holdDte.ToString & "'") ((( I get an error on the web page
when I click on a date saying that the table column
[doc_dte_due] isn't found ?? )))

ListBox1.Items.Clear()

For Each irow In nRow
ListBox1.Items.Add(irow("case_id") & " " &
irow("Document_Nme"))
Next

ListBox1.DataBind() (((( Do I need this ? )))

End Sub
 
ListBox1.DataBind() (((( Do I need this ? )))
No you don't

A dataset is an in-memory representation of the datasource. A datatable is
representation of a particular table. So there wouldn't really be a
dataset-table.

For the select to work it has to work on the actual name of the column so if
your select used "column_date" then you would not be allowed to use column1
you would have to use the "column_date" string to identify the column.

What you will need to do is something like this, since the dataset is
already stored in dsCases, just retrieve it and bind it to the listbox,
there is no need to go back to the database for it.

//c# code btw
//pull it out of session and cast it back as a dataset because it is plain
object
DataSet ds = (DataSet) Session("dsCases")

//tell it which field you want to display in the listbox because it doesnt
know
ListBox1.DataTextField = "column_name_from_select_query"

//tell it where the data is
ListBox1.DataSource = ds;

//then tell it to display itself
ListBox1.DataBind()



--
Regards,
Alvin Bruney
Got Tidbits? Get it here
www.networkip.net/tidbits
Gordon said:
Hi;

I am a novice asp.net developer who would like to create
a dataset-table and then use the datatable.select cmd. to
look up a value passed from the web calender control. The
value(s) would then be used to populate a listbox on a
web form. I keep getting an error that says that in the
datatable.SELECT statement i.e. mytable.select("column1 =
= '" & aVariable & "'"), that the column1 can't be found.
I can run this program code in a windows program and it
works fine. What am I missing, code wise, to make the
code run under ASP.net ?

Here is the following code that I tried. It is
called from the date selected event of the web calender
control.

Thanks,

Gordon

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

Public Sub SetUpDataBinding()

Dim datConn As String = "Integrated
Security=SSPI;Initial Catalog=DocsDates;Data Source=
(local)\vsdotnet"
Dim cnDocDates As New SqlConnection(datConn)

Try

Dim cmdGetCases As New SqlCommand
("CMasterSelectCommand", cnDocDates)
Dim daCases As New SqlDataAdapter("SELECT
case_id, lname, case_status from CaseMaster", cnDocDates)
Dim daDocs As New SqlDataAdapter("SELECT
case_id, document_nme, doc_dte_start, " & _
"doc_dte_due, comments from CaseDocs where
case_id in " & _
"(SELECT case_id from CaseMaster)",
cnDocDates)
Dim ds As New DataSet
daDocs.Fill(dsCases, "tblCaseDocs")
Session("dsCases") = dsCases

holdDte = Today


Catch ex As System.Data.SqlClient.SqlException

If
HttpContext.Current.Request.UserHostAddress = "129.0.0.5"
Then
Session("CurrentError") = ex.Message
Else
Session("CurrentError") = "Error
processing page."
End If
Server.Transfer("ApplicationError.aspx")
Finally
' cnDocDates.Close()
End Try

End Sub


Public Sub ListBoxFill() ((( This called when a date
is selected on the calendar web control )))))

Dim myCol As DataColumn
Dim myRow As DataRow
Dim currRows() As DataRow


Dim nRow As DataRow()
Dim irow As DataRow

nRow = tblCaseDocs.Select("doc_dte_due = '" &
holdDte.ToString & "'") ((( I get an error on the web page
when I click on a date saying that the table column
[doc_dte_due] isn't found ?? )))

ListBox1.Items.Clear()

For Each irow In nRow
ListBox1.Items.Add(irow("case_id") & " " &
irow("Document_Nme"))
Next

ListBox1.DataBind() (((( Do I need this ? )))

End Sub
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