Vba Windows窗体应用程序如何从列表框添加项目

我有一个任务来创建一个简单的快餐点餐系统，我成功地为列表框中的项目分配了值，但是每次我按下按钮下订单时，它并不总是将所选项目相加

Public Class FastFoodPizza
Dim cheesepizza, pepperonipizza, meatpizza, margheritapizza, bbqchickenpizza As Decimal
Dim thinbase, thickbase As Decimal
Dim large, medium, small As Decimal
Dim total As Decimal
Private Sub LtbPizzChoices_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ltbPizzChoices.SelectedIndexChanged

    ltbPizzChoices.SelectionMode = SelectionMode.MultiSimple


End Sub

Private Sub GrbBase_Enter(sender As Object, e As EventArgs) Handles grbBase.Enter

End Sub



Private Sub BtnPlaceorder_Click(sender As Object, e As EventArgs) Handles btnPlaceorder.Click

    For Each item As String In ltbPizzChoices.SelectedItems
        If item = "Cheese Pizza" Then
            cheesepizza = 7.99

        End If
        If item = "Pepperoni Pizza" Then
            pepperonipizza = 8.99
            
        End If
        If item = "Meat Pizza" Then
            meatpizza = 9.49

        End If
        If item = "Margherita Pizza" Then
            margheritapizza = 7.49

        End If
        If item = "BBQ Chicken Pizza" Then
            bbqchickenpizza = 10.5

        End If
    Next


    txtTotal.Text = (cheesepizza + pepperonipizza + meatpizza + margheritapizza + bbqchickenpizza)

End Sub

Private Sub TxtTotal_TextChanged(sender As Object, e As EventArgs) Handles txtTotal.TextChanged

End Sub

---

下课

我想我们不是来帮你做作业的，但是

您的代码可能会将

txtotal.Text

的值设置为仅最近的选择，而不是与以前的选择相符（如果这是您的目标），因为（猜测）您的列表框可能设置为单一选择

您（可能）需要设置一个静态或模块变量来保存单个选择和订单总数

有许多方法可以改进您的代码：

创建一个比萨饼类（名称、价格、基数、大小、属性等）并从中派生比萨饼类型

如果s，使用

Case Select

而不是multiple

If

s

您有一个空的

txtotal.TextChanged

处理程序

等等