SqlConnection c = new SqlConnection(MainForm.connection);
      c.Open();
        SqlCommand cmd = new SqlCommand("SELECT id, ragione_sociale, indirizzo, cap, città, provincia FROM cliente", c);
         c.Close();
        da = new SqlDataAdapter(cmd);
         SqlCommandBuilder cb = new SqlCommandBuilder(da);
        ds = new DataSet();
        da.Fill(ds,"cliente");
        
      txtId.DataBindings.Add("Text",ds,"cliente.id"); 
      txtRagione_sociale.DataBindings.Add("Text",ds,"cliente.ragione_sociale");
    }
    
    void Button1Click(object sender, EventArgs e)
    {
      da.Update(ds, "cliente");
      this.Close();
    }