private void btnConfirm_Click(object sender, EventArgs e)
        {
            if (string.IsNullOrWhiteSpace(tbName.Text) || string.IsNullOrWhiteSpace(tbCalories.Text))
            {
                MessageBox.Show("Fields can't be empty!");
                return;
            }


            using (var fc = new FitLifeDataContent())
            {
                if (_product == null)
                {
                    _product = new Product()
                    {
                        Name = tbName.Text, Calories = int.Parse(tbCalories.Text)
                    };
                    fc.Products.Add(_product);
                }
                else
                {
                    if (_product.Name != tbName.Text)
                    {
                        _product.Name = tbName.Text;
                        changed       = true;
                    }

                    if (_product.Calories != int.Parse(tbCalories.Text))
                    {
                        _product.Calories = int.Parse(tbCalories.Text);
                        changed           = true;
                    }

                    if (changed)
                    {
                        if (DialogResult.OK == MessageBox.Show("Are you sure?", "Product will be changed!", MessageBoxButtons.OKCancel, MessageBoxIcon.Warning))
                        {
                            fc.Entry(_product).State = System.Data.Entity.EntityState.Modified;
                        }
                        else
                        {
                            this.Close();
                        }
                    }
                }

                fc.SaveChanges();
                this.Close();
            }
        }
        private void btnConfirm_Click(object sender, EventArgs e)
        {
            if (string.IsNullOrWhiteSpace(tbName.Text))
            {
                MessageBox.Show("Enter dish Name!");
                return;
            }

            if (lbIngredients.Items.Count == 0)
            {
                MessageBox.Show("Choose ingridients");
                return;
            }

            string tmpIds = string.Empty;

            foreach (var item in lbIngredients.Items)
            {
                tmpIds += $"{((Product)item).Id} ";  
            }

            tmpIds = tmpIds.Substring(0, tmpIds.Length - 1);

            var dish = new Dish() { Name = tbName.Text, Calories = int.Parse(tbCalories.Text), ProductsIds = tmpIds };

            using (var fc = new FitLifeDataContent())
            {
                if (_dishInfo != null)
                {
                    dish.Id = _dishInfo.Id;

                    if (DialogResult.OK == MessageBox.Show("Are you sure?", "Dish will be changed!", MessageBoxButtons.OKCancel, MessageBoxIcon.Warning))
                        fc.Entry(dish).State = System.Data.Entity.EntityState.Modified;
                    else
                        this.Close();         
                }
                else
                {
                    fc.Dishes.Add(dish);
                }

                fc.SaveChanges();
                this.Close();
            }

        }