estrarre dati da db access

**fbdesign** · 10-10-2007, 11:59

Sto cercando di estrarre dei dati da un piccolo db access.
I passaggi che ho fatto sono i seguenti:
- creato db access di nome collana.mdb, avente 1 tabella con i seguenti campi: id(chiave primaria/contatore), titolo e descrizione;
- salvato db con permessi di scrittura e lettura everyone in wwwroot;
- creato file aspx per estrapolarne i dati con seguente codice:

codice:

<%@ Page Language="VB" ContentType="text/html" ResponseEncoding="iso-8859-1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
</head>
<body>
<%@ using Namespace="System.Data.OleDb" %>
<script runat="server">
private void Page_Load(object sender, System.EventArgs e) 
{ 
  OleDbConnection connDB;
  string sql;
  OleDbCommand cmd; 
  connDB = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; data source=" & server.mappath("collana.mdb");
  connDB.Open();
  sql = "SELECT * FROM libri";
  cmd = new OleDbCommand(sql, connDB);
} 
</script> 
</body>
</html>

Mi aiutate per piacere, mi da quest' errore

:

**fbdesign** · 10-10-2007, 12:04

E' chiaro che sono meno di un principiante, non sono sicuro neanche che il codice che ho inserito va messo nel body...

grazie in anticipo a chi avrà la pazienza di darmi una mano!

**pietro09** · 10-10-2007, 13:07

in c# te lo converti te

codice:

<%@ Page Language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim sb As New StringBuilder()
        Dim r As OleDbDataReader = GetDataReader(StringaConnessioneTest, "select * from regioni")
        Do While r.Read()
            sb.Append(NullToString(r.Item("nome_regione")))
            sb.Append("
")
        Loop
        r.Close()
        Me.div1.InnerHtml = sb.ToString()
    End Sub
    
    
    Private ReadOnly Property StringaConnessioneTest() As String
        Get
            Return String.Format("Provider=Microsoft.Jet.OLEDB.4.0;Password="""";User ID=Admin;Data Source={0};Mode=Share Deny None;Extended Properties="""";Jet OLEDB:System database="""";Jet OLEDB:Registry Path="""";Jet OLEDB:Database Password="""";Jet OLEDB:Engine Type=5;Jet OLEDB:Database Locking Mode=1;Jet OLEDB:Global Partial Bulk Ops=2;Jet OLEDB:Global Bulk Transactions=1;Jet OLEDB:New Database Password="""";Jet OLEDB:Create System Database=False;Jet OLEDB:Encrypt Database=False;Jet OLEDB:Don't Copy Locale on Compact=False;Jet OLEDB:Compact Without Replica Repair=False;Jet OLEDB:SFP=False", "C:\DATI\test\test.mdb")
        End Get
    End Property

    Private Function GetDataReader(ByVal stringaConnessione As String, ByVal stringaSQL As String) As OleDbDataReader
        Dim Reader As OleDbDataReader = Nothing
        Dim Connessione As OleDbConnection = Nothing
        Try
            Connessione = New OleDbConnection(stringaConnessione)
            Connessione.Open()
            Dim Comando As New OleDbCommand(stringaSQL, Connessione)
            Reader = Comando.ExecuteReader(CommandBehavior.CloseConnection)
            Return Reader
        Catch Errore As Exception
            Connessione.Close()
            Throw
        End Try


    End Function

    Private Function NullToString(ByVal v As Object) As String
        If IsDBNull(v) Then
            Return ""
        Else
            Return CType(v, String)
        End If

    End Function

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Pagina senza titolo</title>
</head>
<body>
    <form id="form1" runat="server">
    <div id="div1" runat="server"></div>
    </form>
</body>
</html>

**fbdesign** · 10-10-2007, 13:24

Grazie Pietro gentilissimo...
Perchè dici di convertirlo in c#?
Io cmq ho provato ad utilizzarlo modificando i nomi dei file ed i percorsi in questo modo:

codice:

<%@ Page Language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim sb As New StringBuilder()
        Dim r As OleDbDataReader = GetDataReader(StringaConnessioneTest, "select * from collana")
        Do While r.Read()
            sb.Append(NullToString(r.Item("titolo")))
            sb.Append("
")
        Loop
        r.Close()
        Me.div1.InnerHtml = sb.ToString()
    End Sub
    
    
    Private ReadOnly Property StringaConnessioneTest() As String
        Get
            Return String.Format("Provider=Microsoft.Jet.OLEDB.4.0;Password="""";User ID=Admin;Data Source={0};Mode=Share Deny None;Extended Properties="""";Jet OLEDB:System database="""";Jet OLEDB:Registry Path="""";Jet OLEDBatabase Password="""";Jet OLEDB:Engine Type=5;Jet OLEDBatabase Locking Mode=1;Jet OLEDB:Global Partial Bulk Ops=2;Jet OLEDB:Global Bulk Transactions=1;Jet OLEDB:New Database Password="""";Jet OLEDB:Create System Database=False;Jet OLEDB:Encrypt Database=False;Jet OLEDBon't Copy Locale on Compact=False;Jet OLEDB:Compact Without Replica Repair=False;Jet OLEDB:SFP=False", "C:\Inetpub\wwwroot\collana.mdb")
        End Get
    End Property

    Private Function GetDataReader(ByVal stringaConnessione As String, ByVal stringaSQL As String) As OleDbDataReader
        Dim Reader As OleDbDataReader = Nothing
        Dim Connessione As OleDbConnection = Nothing
        Try
            Connessione = New OleDbConnection(stringaConnessione)
            Connessione.Open()
            Dim Comando As New OleDbCommand(stringaSQL, Connessione)
            Reader = Comando.ExecuteReader(CommandBehavior.CloseConnection)
            Return Reader
        Catch Errore As Exception
            Connessione.Close()
            Throw
        End Try


    End Function

    Private Function NullToString(ByVal v As Object) As String
        If IsDBNull(v) Then
            Return ""
        Else
            Return CType(v, String)
        End If

    End Function

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Pagina senza titolo</title>
</head>
<body>
    <form id="form1" runat="server">
    <div id="div1" runat="server"></div>
    </form>
</body>
</html>

l'ERRORE ORA è QUESTO

:

**pietro09** · 10-10-2007, 13:28

nel web config ho:

<add namespace="System.Data"/>
<add namespace="System.Data.OleDb"/>

altrimenti aggiungi all'inizio pagina

<%@ Import Namespace="System.Data"%>
<%@ Import Namespace="System.Data.OleDb"%>

**fbdesign** · 10-10-2007, 14:41

Mi da questo:

**fbdesign** · 11-10-2007, 10:01

Grazie per l'aiuto ho risolto!!!
Posto in codice, magari potrà servire a qualcun'altro...

codice:

<%@ Page Language="VB" ValidateRequest="false" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.OleDb" %>
<script runat="server">
    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs)
        ' Creo un oggetto connection, command e datareader del namespace OleDB
        Dim cn As OleDbConnection
        Dim cmd As OleDbCommand
        Dim dr As OleDbDataReader
        ' Apro la connessione
        Dim str As String = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=" & Server.MapPath("collana.mdb")
        cn = New OleDbConnection(str)
        cn.Open()
        ' Lancio una query nell'oggetto commando di OleDB
        cmd = New OleDbCommand("SELECT * FROM libri", cn)
        ' Eseguo la query in un datareader
        dr = cmd.ExecuteReader()
        ' Mostro i dati a video
        While (dr.Read())
            libri.Text += dr("titolo") & " " & dr("descrizione") & "
"
        End While
        ' Un po di pulizia...
        dr.Close()
        cn.Close()
    End Sub
</script>
<html>
    <head>
        <title>Utilizzo di ADO.NET</title>
    </head>
<body>

<form id="Modulo" runat="server">
    <asp:Label id="libri" runat="server" />
</form>

</body>
</html>

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