protected void Page_Load(object sender, EventArgs e)
    {
       
        string connectionString = ConfigurationManager.ConnectionStrings["provaConnectionString4"].ConnectionString;
        SqlConnection conn = new SqlConnection(connectionString);
        SqlCommand comm = conn.CreateCommand();
        string sql1;
        string field = Request.QueryString["inserto"])
        sql1 = String.Format("Select tipologia, id, immagine, attacco from prodotti where inserto = '{0}'", field);

       
        DataSet ds = new DataSet();
        SqlDataAdapter da;
        da = new SqlDataAdapter(sql1, conn);       
        da.Fill(ds, "prodotti");       
        GridView1.DataSource = ds.Tables[0];
        GridView1.DataBind();

    }