codice:Public Class DBgest
    Private _sql As String
    Private _contarighe As String
    Private cn As New SqlConnection()
    Public Property sql() As String
        Get
            Return _sql
        End Get
        Set(ByVal value As String)
            _sql = value
        End Set
    End Property
    Public Function apridati() As SqlDataReader
        Dim mytable As New DataTable
        Dim datiletti As SqlDataReader
        Dim cmd As New SqlCommand
        cn = New SqlConnection
        cn.ConnectionString = ConfigurationManager.ConnectionStrings("sirio8sql").ConnectionString
        cn.Open()
        cmd.CommandText = _sql
        cmd.CommandType = CommandType.Text
        cmd.Connection = cn
        datiletti = cmd.ExecuteReader(CommandBehavior.CloseConnection)
        Return datiletti
    End Function
    Public Function contarighe() As Integer
        Dim mytable As New DataTable
        Dim datiletti
        Dim cmd As New SqlCommand
        cn = New SqlConnection
        cn.ConnectionString = ConfigurationManager.ConnectionStrings("sirio8sql").ConnectionString
        cn.Open()
        cmd.CommandText = _sql
        cmd.CommandType = CommandType.Text
        cmd.Connection = cn
        datiletti = cmd.ExecuteReader(CommandBehavior.CloseConnection)
        mytable.Load(datiletti)
        Return mytable.Rows.Count
    End Function
    Public Function esegui() As Integer
        Dim nraffected As Integer
        Dim cmd As SqlCommand
        cn = New SqlConnection
        cn.ConnectionString = ConfigurationManager.ConnectionStrings("sirio8sql").ConnectionString
        cn.Open()
        cmd = New SqlCommand
        cmd.CommandText = _sql
        cmd.CommandType = CommandType.Text
        cmd.Connection = cn
        nraffected = cmd.ExecuteNonQuery()
        Return nraffected
    End Function
    Public Function nonull(ByVal valore, ByVal restituzione)
        If valore Is DBNull.Value Then
            Return restituzione
        Else
            Return valore
        End If
    End Function
    Public Function nonullorblank(ByVal valore, ByVal restituzione)
        If valore Is DBNull.Value Then
            Return restituzione
        Else
            If Trim(valore) = "" Then
                Return restituzione
            Else
                Return valore
            End If
        End If
    End Function
    Public Function estrai(ByVal colonna As String, ByVal tabella As String, ByVal campo_indice As String, ByVal valore_indice As String) As String
        Dim datiletti As SqlDataReader
        Dim cmd As New SqlCommand
        Dim valore As String = ""
        cn = New SqlConnection
        cn.ConnectionString = ConfigurationManager.ConnectionStrings("sirio8sql").ConnectionString
        cn.Open()
        cmd.CommandText = "select " & colonna & " from " & tabella & " where " & campo_indice & "=" & valore_indice
        'HttpContext.Current.Response.Write(cmd.CommandText)
        'HttpContext.Current.Response.End()
        cmd.Connection = cn
        datiletti = cmd.ExecuteReader(CommandBehavior.CloseConnection)
        For Each i In datiletti
            valore = datiletti(colonna).ToString
        Next
        cn.Close()
        cn = Nothing
        cmd = Nothing
        Return valore
    End Function
    Public Sub DBchiudi()
        cn.Close()
        cn = Nothing
    End Sub
End Class