I have just started programming in VB.net.
I am recoding an old VB6.0 program to VB.net, and having a problem with
setting a database field back to null.
The VB6.0 code was:
Set rs = OpenTable("select * from tblunits where unit = " & "'" & temp &
"'")
rs!status = "Available"
rs!eventnum = Null
rs.Update
I have tried a number of different way in VB.net but always get errors. Here
is my current code.
Dim sqlda As New SqlDataAdapter
Dim SQLcmd As New SqlCommand
Dim TableFlag As DataTable
Dim drunitstatus As DataRow
With SQLcmd
.Connection = conn
.CommandType = CommandType.Text
.CommandText = ("select * from tblunits where unit = '" & UnitName & "'")
End With
sqlda = New SqlDataAdapter(SQLcmd)
TableFlag = New DataTable
sqlda.Fill(TableFlag)
drunitstatus = TableFlag.Rows(0)
drunitstatus("status") = "Available"
drunitstatus("eventnum") = DBNull.value 'This appear to be the problem line
"eventnum" is int32 and allow nulls
Dim sCB As SqlCommandBuilder = New SqlCommandBuilder(sqlda)
sqlda.Update(TableFlag)
The Current error is "NullReferenceException was Caught"
Can any one advise what I am doing wrong?
Darron
