FIlter DataSet

Public Function crea_dtset(ByVal sql As String, ByVal RiempiDataGrid As Boolean, ByVal SqlFilter As String) As DataSet
        Try
 
            Dim objAdapter As New SqlClient.SqlDataAdapter()
            Dim objDataSet As DataSet
            Dim objConnection As New SqlClient.SqlConnection
            Dim objCommand As SqlClient.SqlCommand
            Dim objDataView As New DataView()
 
 
            'Setto ed apro la connessione
            objConnection.ConnectionString = "Server=myServer\SQLEXPRESS;Database=mydb;User ID=myid;Password=mypwd;Trusted_Connection=False;"
            objConnection.Open()
 
            If (objConnection.State = ConnectionState.Open) Then
 
                'Creo un nuovo oggetto command a cui viene passata la nostra stringa
                'sql e i parametri di connessione
                objCommand = New SqlClient.SqlCommand(sql, objConnection)
                objCommand.CommandText = sql
                objCommand.CommandType = CommandType.Text
 
 
                'Viene Riempito il DataSet
                objAdapter = New SqlClient.SqlDataAdapter(objCommand)
                objDataSet = New DataSet()
                objAdapter.Fill(objDataSet)
 
                objConnection.Close()
 
                crea_dtset = objDataSet
 
                'Filtro i miei dati
 
                If RiempiDataGrid = True Then
                    'Riempio il dataview con l'intero contenuto della mia query
                    objDataView = objDataSet.Tables(0).DefaultView
                    objDataView.RowFilter = sqlFilter
 
                    'Assegno come datasource l'oggetto objdataview(filtrato)
                    frmMain.DGVDati.DataSource = objDataView
                End If
 
                'Svuoto gli oggetti per la prossima query
                objDataView = Nothing
                objAdapter = Nothing
                objCommand = Nothing
                objDataSet = Nothing
                objConnection = Nothing
            End If
 
 
 
        Catch ex As Exception
 
            MsgBox("Error!")
 
        End Try
    End Function