Datagrid wpf

private fatturaEntities ctx;
public ObservableCollection<corpo> cr2;
    public MainWindow()
    {
      InitializeComponent();
       this.ctx = new fatturaEntities();
       this.cr2 = new ObservableCollection<corpo>();
       grdCorpo.ItemsSource = cr2;
    }

    private void btnInserisci_Click(object sender, RoutedEventArgs e)
    {
      this.grdCorpo.IsEnabled = true;
      corpo cr = new corpo();
      this.ctx.AddTocorpo(cr);
       this.cr2.Add(cr);
      // grdCorpo.ItemsSource = cr2;
    }

    private void btnRicerca_Click(object sender, RoutedEventArgs e)
    {
      //ricerca per id
      try
      {
        int ric = Convert.ToInt32(txtricerca.Text);
        var loadedLog = ctx.corpo.Where(ent => ent.idcorpo == ric).ToList();
        grdCorpo.ItemsSource = loadedLog;
      }
      catch (Exception ex)
      {
        MessageBox.Show(ex.Message);
      }
    }

public int Guadagno
{
   get {  return Ricavi - Spese; }
}

...

public int Ricavi { get; set; }
public int Spese { get; set; }
...

    public class OrdineItem : OggettoBase , INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;
        void RaiseChanged(string proprieta)
        {
            if (PropertyChanged != null)
                PropertyChanged(this, new PropertyChangedEventArgs(proprieta));
        }


        DateTime data;
        public DateTime Data {
            get { return data; }
            set { 
                data = value;
                RaiseChanged("Data");
            }
        }


        decimal prezzo;
        public decimal Prezzo
        {
            get { return prezzo; }
            set
            {
                prezzo = value;
                RaiseChanged("Prezzo");
                RaiseChanged("Costo");
            }
        }


        decimal pesoNetto;
        public decimal PesoNetto
        {
            get { return pesoNetto; }
            set
            {
                pesoNetto = value;
                RaiseChanged("PesoNetto");
                RaiseChanged("Costo");
            }
        }



        public decimal Costo
        {
            get {
                return PesoNetto * Prezzo;
            }
        }

        
    }

public class ClienteDataProvider
{

        public IEnumerable<Cliente> GetAll()
        {
            List<Cliente> lista = new List<Cliente>();

            using (SqlConnection cn = new SqlConnection(....))
            {
                SqlCommand cmd = cn.CreateCommand();
                cmd.CommandText = "SELECT ... FROM...";

                cn.Open();
                SqlDataReader rd = cmd.ExecuteReader();
                while(rd.Read())
                      lista.Add(BuildCliente(rd));
            }

            return lista;
        }

        private Cliente BuildCliente(SqlDataReader rd)
        {     
                Cliente c = new Cliente();
                c.Id = Convert.ToInt32(rd["nomecampoID"]);
                c.Nome = Convert.ToString(rd["nomecampoNome"]);
               .... etc ...
                return c; 
        }
...
}

        [EdmScalarPropertyAttribute(EntityKeyProperty=false, IsNullable=true)]
        [DataMemberAttribute()]
        public Nullable<global::System.Int32> pnetto
        {
            get
            {
                return _pnetto;
            }
            set
            {
                OnpnettoChanging(value);
                ReportPropertyChanging("pnetto");
                _pnetto = StructuralObject.SetValidValue(value);
                ReportPropertyChanged("pnetto");
                OnpnettoChanged();
            }
        }
        private Nullable<global::System.Int32> _pnetto;
        partial void OnpnettoChanging(Nullable<global::System.Int32> value);
        partial void OnpnettoChanged();


 [EdmScalarPropertyAttribute(EntityKeyProperty=false, IsNullable=true)]
        [DataMemberAttribute()]
        public Nullable<global::System.Int32> prezzo
        {
            get
            {
                return _prezzo;
            }
            set
            {
                OnprezzoChanging(value);
                ReportPropertyChanging("prezzo");
                _prezzo = StructuralObject.SetValidValue(value);
                ReportPropertyChanged("prezzo");
                OnprezzoChanged();
            }
        }
        private Nullable<global::System.Int32> _prezzo;
        partial void OnprezzoChanging(Nullable<global::System.Int32> value);
        partial void OnprezzoChanged();


       [EdmScalarPropertyAttribute(EntityKeyProperty=false, IsNullable=true)]
        [DataMemberAttribute()]
        public Nullable<global::System.Int32> imp
        {
            get
            {
                return _imp;
            }
            set
            {
                OnimpChanging(value);
                ReportPropertyChanging("imp");
                _imp = StructuralObject.SetValidValue(value);
                ReportPropertyChanged("imp");
                OnimpChanged();
            }
        }
        private Nullable<global::System.Int32> _imp;
        partial void OnimpChanging(Nullable<global::System.Int32> value);
        partial void OnimpChanged();