If using SQL Server, you can also address this problem
using either the ISNULL() or COALESCE() functions in the SELECT
statement.
SELECT ISNULL(<<column>>,'') as <<column>> will return an empty
string if the <<column>> is null. Remember to alias the ISNULL()
function as the same name as the column being tested.
SELECT COALESCE(<<column>>,'') as <<column>> will return an empty
string if the <<column>> is null. Likewise, remember to alias the
COALESCE() function the same name as the column being tested.
Dallas Martin
Quoting Dean Fiala <[EMAIL PROTECTED]>:
> The value in this field
>
> dtAllEmployees.Rows(rowcounter).Item("Employee")
>
> contains a DBNull.Value
>
> which means the value in the row for the column Employee is Null and cannot
>
> be cast to a string
>
> I find it helpful to create a shared function to deal with this...
>
> Public Shared Function NullToEmptyString(ByVal o As Object) As String
> If o Is DBNull.Value Then
> Return ""
> Else
> Return o
> End If
> End Function
>
>
> On 9/2/05, Ali Husain <[EMAIL PROTECTED]> wrote:
> >
> > Sorry.... I submitted it by mistake....
> >
> >
> >
> >
> >
> > Hi guys... need an extra set of eyes here:
> >
> >
> >
> > CAST FROM TYPE DBNULL TO STRING ERROR
> >
> >
> >
> > The dt is filled :
> >
> >
> >
> > strConn = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
> >
> > "Data Source=" &
> > Server.MapPath("../database/DermaCareCalls.mdb;")
> >
> > myConn = New OleDb.OleDbConnection(strConn)
> >
> > myConn.Open()
> >
> >
> >
> > mySql = "SELECT loginname from login where clinic = " & "'"
> > & Request("clinic") & "'"
> >
> > myComm = New OleDb.OleDbCommand(mySql, myConn)
> >
> > myadapter = New OleDb.OleDbDataAdapter(mySql, myConn)
> >
> > myadapter.Fill(dtAllEmployees)
> >
> >
> >
> >
> >
> > I even tested to make sure the dataset is filled: Dim testrows As
> > Integer = dtAllEmployees.Rows.Count
> >
> > And it is.
> >
> >
> >
> >
> >
> > For Each row In dtAllEmployees.Rows
> >
> >
> >
> > Dim rowcounter As Integer
> >
> > Dim colcounter As Integer
> >
> > For Each nestedrow In dtDates.Rows
> >
> > Dim calls As Integer
> >
> > Dim sales As Integer
> >
> >
> >
> > Dim employee As String =
> > dtAllEmployees.Rows(rowcounter).Item("Employee") BREAKS HERE
> > <<--------
> >
> >
> >
> >
> >
> > Dim currentDate As Date =
> > dtDates.Rows(rowcounter).Item(0)
> >
> > dtUnformattedCallStats.Select("Employee =" &
> > employee & " and calldate = " & currentDate)
> >
> > dtUnformattedSalesStats.Select("Employee =" &
> > employee & " and calldate = " & currentDate)
> >
> >
> >
> > If Not
> > IsDBNull(dtUnformattedCallStats.Rows.Item(rowcounter).Item("callcount"))
> > Then
> >
> > calls =
> > dtUnformattedCallStats.Rows.Item(rowcounter).Item("callcount")
> >
> > Else
> >
> > calls = 0
> >
> > End If
> >
> >
> >
> > If Not
> > IsDBNull(dtUnformattedSalesStats.Rows.Item(rowcounter).Item("callcount")
> > ) Then
> >
> > sales =
> > dtUnformattedSalesStats.Rows.Item(rowcounter).Item("callcount")
> >
> > Else
> >
> > sales = 0
> >
> > End If
> >
> >
> >
> >
> >
> > ********* CODE TO WRITE TO PDF FILE
> >
> >
> >
> > Blah blah blah
> >
> >
> >
> > rowcounter += 1
> >
> > Next
> >
> > colcounter += 1
> >
> > Next
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> >
> >
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
> >
>
>
> --
> Dean Fiala
> Very Practical Software, Inc
> http://www.vpsw.com
>
>
> [Non-text portions of this message have been removed]
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
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