questo di sotto è un esempio estremamente semplice e semplificato
Un link in una pagina è di questo tipo:

codice:
http://localhost/ArchivioEsempi/prove/a.aspx?id_regione=20
la pagina a.aspx legge id_regione e mostra le province corrispondenti, lette da un database

codice:
<%@ Page Language="VB" AutoEventWireup="false" CodeFile="a.aspx.vb" Inherits="prove_a" %>

<!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 id="Head1" runat="server">
    <title></title>
    <link href="../App_Themes/classico10/StyleSheet.css" rel="stylesheet" type="text/css" />

</head>
<body>
    <form id="form1" runat="server">
    <div  class="a_colore_grigio">
        
        <asp:PlaceHolder ID="PlaceHolder1" runat="server"></asp:PlaceHolder>
        
    </div>
    </form>

</body>
</html>

codice
codice:
Option Strict On
Imports o = Oracle.DataAccess.Client

Partial Class prove_a
    Inherits System.Web.UI.Page


    Protected Sub Page_Load(sender As Object, e As System.EventArgs) Handles Me.Load
        Using con As New o.OracleConnection(gl.StringaConnessioneORA_PIETRO)
            con.Open()
            Using Command As o.OracleCommand = con.CreateCommand()
                Dim id_regione As String = Me.Request.QueryString("id_regione")
                If id_regione = "" Then
                    Me.PlaceHolder1.Controls.Add(New LiteralControl("Passare id_regione per ottenere l'elenco delle province"))
                    Return
                End If

                Command.CommandText = String.Format("select * from province where id_regione = {0}", id_regione)

                Using reader As o.OracleDataReader = Command.ExecuteReader()
                    Dim g As New GridView()
                    g.DataSource = reader
                    g.DataBind()

                    Me.PlaceHolder1.Controls.Add(g)
                End Using
            End Using
        End Using

    End Sub




End Class