NumericUpDown价值*价格附加

Question

我正在创建一个比萨饼菜单，我在我的windows窗体应用程序上有numericUpDown对象，当我将Cheese Pizza的numericUpDown值更改为1时，它会输出in 3.50到总账单标签中，但是当我更改火腿比萨的numericUpDown值时，它会将标签中的文本替换为in 4.20。当我有1x Cheese Pizza和1x Ham Pizza时，如何将总数相加，得出1x Cheese Pizza和1x Ham Pizza的£7.70

private void NudQuantity1_ValueChanged(object sender, EventArgs e)
{
  if (NudQuantity1.Value == 0)
  {
    gbCheesePizza.Enabled = false;
  }
  else
  {
    gbCheesePizza.Enabled = true;
  }
  Total = Convert.ToDouble(NudQuantity1.Value) * Price_CheesePizza;
  lblTotalBill.Text = String.Format("{0:C}", Total);
}

private void NudQuantity2_ValueChanged(object sender, EventArgs e)
{
  if (NudQuantity2.Value == 0)
  {
    gbHamPizza.Enabled = false;
  }
  else
  {
    gbHamPizza.Enabled = true;
  }
  Total = Convert.ToDouble(NudQuantity2.Value) * Price_HamPizza;
  lblTotalBill.Text = String.Format("{0:C}", Total);
}

Answer 1

这两个事件都应该调用一个公共方法来重新计算两个数量的总和

private void NudQuantity1_ValueChanged(object sender, EventArgs e)
{

    gbCheesePizza.Enabled = !(NudQuantity1.Value == 0)
    UpdateTotal();

}

private void NudQuantity2_ValueChanged(object sender, EventArgs e)
{
    gbHamPizza.Enabled = !(NudQuantity2.Value == 0)
    UpdateTotal();
}
private void UpdateTotal()
{
    Total = Convert.ToDouble(NudQuantity1.Value) * Price_CheesePizza;
    Total += Convert.ToDouble(NudQuantity2.Value) * Price_HamPizza;
    lblTotalBill.Text = $"{Total:C}";
}

Answer 2

您每次都会覆盖您的合计。当您添加项目时，请随身携带。

简单的例子

    Total = Total + (Convert.ToDouble(NudQuantity2.Value) * Price_HamPizza)

使用它可以让它工作，无论商品的数量或订购顺序如何。