Question

我创建了一个简单的比萨计划（针对夏季项目而非教育相关），它使用复选框来确定客户想要的内容。基本上是一个简单的披萨订购计划。我想知道因为我已经使用了If语句而不是其他参数和变量，是否可以使用乘法数组来简单地使用VB代码......

我被建议在VB.Net中使用Constructors，但目前没有经验，你能帮忙吗？或者有更简单的方法来创建这个程序......或者更好的编程方式？如何减少代码中的重复？

Option Strict On
Public Class Form1

Dim CurrentBalance As String
Private Sub CheckBox1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged

    Dim SmallPizza As String
    SmallPizza = "5"
    CurrentBalance = Label4.Text
    If CheckBox1.Checked Then
        ListBox1.Items.Add("Small Pizza")
        Label4.Text = CStr(Val(CurrentBalance) + Val(SmallPizza))
    Else
        ListBox1.Items.Remove("Small Pizza")
        Label4.Text = CStr(Val(CurrentBalance) - Val(SmallPizza))
    End If
End Sub

Private Sub CheckBox2_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox2.CheckedChanged
    Dim MediumPizza As String
    MediumPizza = "7"
    CurrentBalance = Label4.Text
    If CheckBox2.Checked Then
        ListBox1.Items.Add("Medium Pizza")
        Label4.Text = CStr(Val(CurrentBalance) + Val(MediumPizza))
    Else
        ListBox1.Items.Remove("Medium Pizza")
        Label4.Text = CStr(Val(CurrentBalance) - Val(MediumPizza))
    End If
End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    CurrentBalance = Label4.Text
    MessageBox("Total cost: £" & CurrentBalance)
End Sub

Private Sub CheckBox3_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox3.CheckedChanged
    Dim LargePizza As String
    LargePizza = "9"
    CurrentBalance = Label4.Text
    If CheckBox3.Checked Then
        ListBox1.Items.Add("Large Pizza")
        Label4.Text = CStr(Val(CurrentBalance) + Val(LargePizza))
    Else
        ListBox1.Items.Remove("Large Pizza")
        Label4.Text = CStr(Val(CurrentBalance) - Val(LargePizza))
    End If
End Sub

Private Sub CheckBox4_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox4.CheckedChanged
    Dim ExtraLargePizza As String
    ExtraLargePizza = "7"
    CurrentBalance = Label4.Text
    If CheckBox4.Checked Then
        ListBox1.Items.Add("Extra Large Pizza")
        Label4.Text = CStr(Val(CurrentBalance) + Val(ExtraLargePizza))
    Else
        ListBox1.Items.Remove("Extra Large Pizza")
        Label4.Text = CStr(Val(CurrentBalance) - Val(ExtraLargePizza))
    End If
End Sub

Private Sub CheckBox5_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox5.CheckedChanged
    Dim Ham As String
    Ham = "1"
    CurrentBalance = Label4.Text
    If CheckBox5.Checked Then
        ListBox1.Items.Add("Ham")
        Label4.Text = CStr(Val(CurrentBalance) + Val(Ham))
    Else
        ListBox1.Items.Remove("Ham")
        Label4.Text = CStr(Val(CurrentBalance) - Val(Ham))
    End If
End Sub

Private Sub CheckBox6_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox6.CheckedChanged
    Dim Pineapple As String
    Pineapple = "1"
    CurrentBalance = Label4.Text
    If CheckBox6.Checked Then
        ListBox1.Items.Add("Pineapple")
        Label4.Text = CStr(Val(CurrentBalance) + Val(Pineapple))
    Else
        ListBox1.Items.Remove("Pineapple")
        Label4.Text = CStr(Val(CurrentBalance) - Val(Pineapple))
    End If
End Sub

Private Sub CheckBox7_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox7.CheckedChanged
    Dim Bananna As String
    Bananna = "1"
    CurrentBalance = Label4.Text
    If CheckBox7.Checked Then
        ListBox1.Items.Add("Bananna")
        Label4.Text = CStr(Val(CurrentBalance) + Val(Bananna))
    Else
        ListBox1.Items.Remove("Bananna")
        Label4.Text = CStr(Val(CurrentBalance) - Val(Bananna))
    End If
End Sub

Private Sub CheckBox8_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox8.CheckedChanged
    Dim Meat As String
    Meat = "1"
    CurrentBalance = Label4.Text
    If CheckBox8.Checked Then
        ListBox1.Items.Add("Meat")
        Label4.Text = CStr(Val(CurrentBalance) + Val(Meat))
    Else
        ListBox1.Items.Remove("Meat")
        Label4.Text = CStr(Val(CurrentBalance) - Val(Meat))
    End If
End Sub

Private Sub CheckBox9_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox9.CheckedChanged
    Dim ExtraCheese As String
    ExtraCheese = "1"
    CurrentBalance = Label4.Text
    If CheckBox9.Checked Then
        ListBox1.Items.Add("Extra Cheese")
        Label4.Text = CStr(Val(CurrentBalance) + Val(ExtraCheese))
    Else
        ListBox1.Items.Remove("Extra Cheese")
        Label4.Text = CStr(Val(CurrentBalance) - Val(ExtraCheese))
    End If
End Sub

Private Sub CheckBox10_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox10.CheckedChanged
    Dim Pepperoni As String
    Pepperoni = "1"
    CurrentBalance = Label4.Text
    If CheckBox10.Checked Then
        ListBox1.Items.Add("Pepperoni")
        Label4.Text = CStr(Val(CurrentBalance) + Val(Pepperoni))
    Else
        ListBox1.Items.Remove("Pepperoni")
        Label4.Text = CStr(Val(CurrentBalance) - Val(Pepperoni))
    End If
End Sub

Private Sub CheckBox11_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox11.CheckedChanged
    Dim Special As String
    Special = "1"
    CurrentBalance = Label4.Text
    If CheckBox11.Checked Then
        ListBox1.Items.Add("Special")
        Label4.Text = CStr(Val(CurrentBalance) + Val(Special))
    Else
        ListBox1.Items.Remove("Special")
        Label4.Text = CStr(Val(CurrentBalance) - Val(Special))
    End If
End Sub

Private Sub CheckBox12_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox12.CheckedChanged
    Dim Pickup As String
    Pickup = "1"
    CurrentBalance = Label4.Text
    If CheckBox12.Checked Then
        ListBox1.Items.Add("Pickup")
        Label4.Text = CStr(Val(CurrentBalance) - Val(Pickup))
    Else
        Label4.Text = CStr(Val(CurrentBalance) + Val(Pickup))
        ListBox1.Items.Remove("Pickup")
    End If
End Sub

Private Sub CheckBox13_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox13.CheckedChanged
    Dim Deliver As String
    Deliver = "5"
    CurrentBalance = Label4.Text
    If CheckBox13.Checked Then
        ListBox1.Items.Add("Deliver")
        Label4.Text = CStr(Val(CurrentBalance) + Val(Deliver))
    Else
        Label4.Text = CStr(Val(CurrentBalance) - Val(Deliver))
        ListBox1.Items.Remove("Deliver")
    End If
End Sub

Private Sub ChesseToastToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ChesseToastToolStripMenuItem.Click
    Dim CheeseToast As String
    CheeseToast = "8"
    CurrentBalance = Label4.Text
    ListBox1.Items.Add("Cheese Toast")
    Label4.Text = CStr(Val(CurrentBalance) + Val(CheeseToast))
End Sub

Private Sub GarlicToastToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles GarlicToastToolStripMenuItem.Click
    Dim GarlicToast As String
    GarlicToast = "11"
    CurrentBalance = Label4.Text
    ListBox1.Items.Add("Garlic Toast")
    Label4.Text = CStr(Val(CurrentBalance) + Val(GarlicToast))
End Sub

Private Sub BreadSticksToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BreadSticksToolStripMenuItem.Click
    Dim Breadsticks As String
    Breadsticks = "14"
    CurrentBalance = Label4.Text
    ListBox1.Items.Add("Bread Sticks")
    Label4.Text = CStr(Val(CurrentBalance) + Val(Breadsticks))
End Sub

Private Sub CashToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CashToolStripMenuItem.Click
    ListBox1.Items.Add("Paying by Cash")
End Sub

Private Sub ChequeToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ChequeToolStripMenuItem.Click
    ListBox1.Items.Add("Paying by Cheque")
End Sub

Private Sub DebitToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles DebitToolStripMenuItem.Click
    ListBox1.Items.Add("Paying by Debit Card")
End Sub

Private Sub CreditCardToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CreditCardToolStripMenuItem.Click
    ListBox1.Items.Add("Paying by Crebit Card")
End Sub

Private Sub VoucherToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles VoucherToolStripMenuItem.Click
    Dim Voucher As String
    Voucher = "5"
    CurrentBalance = Label4.Text
    ListBox1.Items.Add("Voucher")
    Label4.Text = CStr(Val(CurrentBalance) - Val(Voucher))
End Sub

Private Sub ExitToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExitToolStripMenuItem.Click
    End
End Sub

Private Sub MessageBox(ByVal p1 As String)
    Throw New NotImplementedException
End Sub

非常感谢帮助。

Answer 1

VB.NET的一些原理：

始终启用Option Strict（因为我已经看到了恐怖）
您可以直接为这些变量指定值：Dim s As String = "MyString"
帮自己一个忙，从项目中删除Microsoft.VisualBasic - 命名空间并开始使用新类（例如MessageBox而不是MsgBox）。*

到您的项目：一种更好的重构方法可能就是将所有内容都填入Dictionary(Of String, Decimal)，这可能会更好。

Private prices As New Dictionary(Of String, Decimal)
Private balance As Decimal = 0D

' Add this to the constructor '
prices.Add("Ham", 1D)
prices.Add("Banana", 1D)
prices.Add("Pineapple", 1D)
' etc. ... '

For Each item As KeyValuePair(Of String, Decimal) In prices
    CheckedListBox1.Add(item.Key)
Next

' End of Constructor '

' Don't forget to give your Controls meaningful names!
Private Sub CheckedListBox1_ItemCheck(ByVal sender As Object, ByVal e As ItemCheckEventArgs) Handles CheckedListBox1.ItemCheck
    If e.NewValue Then
        balance += prices(CheckedListBox1.Item(e.Index))
    Else
        balance -= prices(CheckedListBox1.Item(e.Index))
    End if

    Label4.Text = balance.ToString("C2")
End Sub

*：正如Konrad Rudolph所指出的，如果您不想包含Forms - 命名空间，这可能是Console-Projects的一个很好的解决方案。虽然，我对此持不同意见。

Answer 2

您可以使用参数添加/删除项目：name，price，checkboxInstance

名称将包含商品名称（凭证，取件，......）
价格将用于更改Label4.Text中的值
checkboxInstance 可帮助您决定要执行的操作：

所以函数的主体看起来像这样：

  If checkboxInstance.Checked Then
       ListBox1.Items.Add(name)
       Label4.Text = Val(CurrentBalance) - Val(price)
  Else
      Label4.Text = Val(CurrentBalance) + Val(price)
      ListBox1.Items.Remove(name)
  End If

我真的不记得VB.NET的语法。但是因为这是你的作业，我想最好提供一个提示而不是代码。

编辑：还有一件事如何从根本上简化代码。您可以使用复选框的“tag”属性来保存商品名称，而不是使用checkbox1，checkbox2，..您可以在Visual Studio的设计器中创建一个复选框数组，以便您可以为它们编制索引（myCheckboxes [0] ，myCheckboxes [1]，...）。 http://www.thevbprogrammer.com/VBNET_09/09-05-ControlArrays.htm - 查看此网站。

Answer 3

某些选项（大小和付款方式）似乎是互斥的，因此您最好将这些RadioButton放在两个单独的GroupBox中。我还建议不要在更新中执行任何计算，而是使用CalculateCost Sub，当成本需要重新计算时，所有事件都会延迟。你应该避免定义，例如ExtraLargePizza作为一个字符串 - 你可以把它变成一个整数（或十进制） - 然后在执行计算时你不需要将它包装在Val（...）中。

Answer 4

您的代码文件似乎有很多重复。您可能需要考虑使用factory pattern来更轻松地创建您正在创建的不同种类的披萨。

祝你好运，并希望这有助于一些人。

是否可以简化（重构）我的比萨程序代码（VB.Net 2010）？

4 个答案: