public override void Delete()
        {
            try
            {
                var item = DataBase.CustomerList.SingleOrDefault(x => x.ID == int.Parse(TxtIDCli.Text));
                if (item != null)
                {
                    MessageBox.Show(TxtNaCli.Text + " Has been Successfully deleted");
                    DataBase.CustomerList.Remove(item);
                    TxtIDCli.Text = "";
                    TxtNaCli.Text = "";
                    TxtAdCli.Text = "";
                    TxtIDCli.Focus();
                }
                else
                {
                    MessageBox.Show(TxtNaCli.Text + " Is not in Our Database");
                    TxtIDCli.Text = "";
                    TxtNaCli.Text = "";
                    TxtAdCli.Text = "";
                    TxtIDCli.Focus();
                }
            }
            catch (Exception error)
            {
                MessageBox.Show("Error" + error);
                TxtIDCli.Text = "";
                TxtNaCli.Text = "";
                TxtAdCli.Text = "";
                TxtIDCli.Focus();
            }


            //DataBase.ProductsList.RemoveAll(x => x.ID == int.Parse(TxtIdPro.Text));
            /*foreach (var c in DataBase.ProductsList)
            {
                if (c.ID == int.Parse(TxtIdPro.Text))
                {
                    MessageBox.Show(TxtDesPro.Text + " Has been Successfully deleted");
                    DataBase.ProductsList.Remove(c);
                    
                }
                else
                {
                    MessageBox.Show(TxtDesPro.Text + " Is not in Our stock");
                }
            }*/
        }
        public override Boolean Save()
        {
            if (string.IsNullOrWhiteSpace(TxtIDCli.Text) || string.IsNullOrWhiteSpace(TxtNaCli.Text) || string.IsNullOrWhiteSpace(TxtAdCli.Text))
            {
                MessageBox.Show("All fields are mandatory", "error", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                return false;
            }
            else
            {
                var item = DataBase.CustomerList.SingleOrDefault(x => x.ID == int.Parse(TxtIDCli.Text));
                if (item == null)
                {

                    try
                    {
                        DataBase.CustomerList.Add(new Customer(int.Parse(TxtIDCli.Text), TxtNaCli.Text, TxtAdCli.Text));
                        MessageBox.Show(TxtNaCli.Text + " has been successfully saved ");
                        TxtIDCli.Text = "";
                        TxtNaCli.Text = "";
                        TxtAdCli.Text = "";
                        TxtIDCli.Focus();
                        return true;
                    }
                    catch (Exception error)
                    {
                        MessageBox.Show("Error" + error);
                        TxtIDCli.Text = "";
                        TxtNaCli.Text = "";
                        TxtAdCli.Text = "";
                        TxtIDCli.Focus();
                        return false;
                    }
                }
                else
                {
                    MessageBox.Show("The custumer with ID " + TxtIDCli.Text + "Already is in the DataBase");
                    TxtIDCli.Text = "";
                    TxtNaCli.Text = "";
                    TxtAdCli.Text = "";
                    return false;
                }
            }
            
        }
        private void button4_Click(object sender, EventArgs e)
        {
            if (string.IsNullOrWhiteSpace(TxtIDCli.Text) || string.IsNullOrWhiteSpace(TxtNaCli.Text) || string.IsNullOrWhiteSpace(TxtAdCli.Text))
            {
                MessageBox.Show("All fields are mandatory", "error", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                
            }
            else
            {
                var item = DataBase.CustomerList.SingleOrDefault(x => x.ID == int.Parse(TxtIDCli.Text));
                if (item != null)
                {

                    try
                    {
                        item.Name = TxtNaCli.Text;
                        item.Address = TxtAdCli.Text;
                        MessageBox.Show(TxtNaCli.Text + " has been successfully updated");
                        TxtIDCli.Text = "";
                        TxtNaCli.Text = "";
                        TxtAdCli.Text = "";
                        TxtIDCli.Focus();
                        
                    }
                    catch (Exception error)
                    {
                        MessageBox.Show("Error" + error);
                        TxtIDCli.Text = "";
                        TxtNaCli.Text = "";
                        TxtAdCli.Text = "";
                        TxtIDCli.Focus();
                        
                    }
                }
                else
                {
                    MessageBox.Show("You cannot Update or change the customer ID");
                    TxtIDCli.Text = "";
                    TxtNaCli.Text = "";
                    TxtAdCli.Text = "";
                }
            }
        }