Buongiorno. Sto cercando di imparare .net utilizzando codice semplice per l'accesso ai dati.
Ho un problema con il datareader che mi restituisce un errore "System.NullReferenceException: Riferimento a un oggetto non impostato su un'istanza di oggetto." proprio sul Reader.Read().
Spero vogliate aiutarmi :)
Imports System
Imports System.Data
Imports System.Configuration
Imports System.Collections
Imports System.Web
Imports System.Web.Security
Imports System.Web.UI
Imports System.Web.UI.Page
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls
Imports System.Data.SqlClient
Partial Public Class DataReader : Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
Dim Reader As SqlDataReader = GetDataReader("SELECT top 10 * FROM informa")
While Reader.Read
Response.Write("<li>" & Reader.Item("id"))
End While
End Sub
Public Function GetDataReader(ByVal query As String) As SqlDataReader
Dim ConnectionString As String = ConfigurationManager.ConnectionStrings("SqlServer").ConnectionString
Dim conn As New SqlConnection(ConnectionString)
conn.Open()
Dim cmd As New SqlCommand(query, conn)
cmd.ExecuteReader(CommandBehavior.CloseConnection)
End Function
End Class
