vb.net - 运行程序后我需要帮助获取正确的值

Question

在 VB.NET 中，我需要：

• 根据售出的门票数量和门票价格计算小计。
• 根据小计计算税金。
• 通过添加税和小计来计算总计。
• 将总计添加到每日总计（运行总计）。
• 计算发起人的利润为每日总计的 20%。
• 显示小计、税收、总计、每日总计和利润。

当我运行程序并在输入售出票数和票价的值后点击提交时，小计和税金恢复正常。但是我总是在 Total Total 和 Daily Grand Total 中得到 0 的值。似乎无法弄清楚为什么。

这是我到目前为止所拥有的：

Private Sub btnSubmit_Click(sender As Object, e As EventArgs) Handles btnSubmit.Click
    Dim intTicketsSold As Integer
    Dim dblTicketPrice As Double
    Const dblTax As Double = 0.07
    Dim dblOATotal As Double
    Dim dblSubTotal As Double
    Dim cdblDGTotal As Double
    Const cdblPromoProfit As Double = 0.2

    'Create local variables
    intTicketsSold = txtTicketsSold.Text
    dblTicketPrice = txtTicketPrice.Text
    lblTax.Text = dblTax
    lblOATotal.Text = dblOATotal
    lblSubTotal.Text = dblSubTotal
    lblDGTotal.Text = cdblDGTotal
    lblPromoProfit.Text = cdblPromoProfit

    'Calculate Subtotal
    lblSubTotal.Text = intTicketsSold * dblTicketPrice

    'calculate tax to subtotal
    lblTax.Text = 0.07 * (intTicketsSold * dblTicketPrice)

    'Get the overall total
    dblOATotal = dblTax + dblSubTotal

    'Add Total to Daily Grand Total to get Running Total

    cdblDGTotal = cdblDGTotal + dblOATotal

    'Calculate Promoters Profit of Daily Grand Total
    lblPromoProfit.Text = 0.2 * cdblDGTotal
End Sub

我究竟做错了什么？

标签： vb.net

Answer 1

Your code is not wrong, but you've forgotten to replace the content of Overall Total label and Daily Grand Total label after calculating their values, and the result of intTicketsSold * dblTicketPrice should be saved in a variable (dblSubtotal) to use it in Overall Total calculation, that way your calculations will be correct. Change your code like below:

Private Sub btnSubmit_Click(sender As Object, e As EventArgs) Handles btnSubmit.Click
    Dim intTicketsSold As Integer
    Dim dblTicketPrice As Double
    Const dblTax As Double = 0.07
    Dim dblOATotal As Double
    Dim dblSubTotal As Double
    Dim cdblDGTotal As Double
    Const cdblPromoProfit As Double = 0.2

    'Create local variables
    intTicketsSold = Convert.ToInt32(txtTicketsSold.Text)
    dblTicketPrice = Convert.ToDouble(txtTicketPrice.Text)
    lblTax.Text = dblTax
    lblSubTotal.Text = dblSubTotal

    lblPromoProfit.Text = cdblPromoProfit

    'Calculate Subtotal
    dblSubTotal = intTicketsSold * dblTicketPrice
    lblSubTotal.Text = dblSubTotal

    'calculate tax to subtotal
    lblTax.Text = 0.07 * (intTicketsSold * dblTicketPrice)

    'Get the overall total
    dblOATotal = dblTax + dblSubTotal
    lblOATotal.Text = dblOATotal
    'Add Total to Daily Grand Total to get Running Total

    cdblDGTotal = cdblDGTotal + dblOATotal
    lblDGTotal.Text = cdblDGTotal
    'Calculate Promoters Profit of Daily Grand Total
    lblPromoProfit.Text = 0.2 * cdblDGTotal
End Sub