方法未返回值[VB.NET]

Question

所以我用构造函数和方法建立了一个基本类，但是我不断得到_TotalCostInteger变量= 0 ，这让我很_TotalCostInteger 。

Public Class FlooringClass
Protected _LengthInteger As Integer
Protected _WidthInteger As Integer
Protected _AreaInteger As Integer
Protected _CustomerNameString As String
Protected _TotalCostInteger As Decimal
Protected _PriceInteger As Integer
Sub New(ByVal LengthIn As Integer, ByVal WidthIn As Integer, ByVal NameIn As String, ByVal PriceIn As Integer)
    Length = LengthIn
    Width = WidthIn
    Name = NameIn
    Price = PriceIn
    CalculateArea()
    CalculateCost()
End Sub
Public Property Length As Integer
    Get
        Return _LengthInteger
    End Get
    Set(value As Integer)
        value = Length
    End Set
End Property
Public Property Width As Integer
    Get
        Return _WidthInteger
    End Get
    Set(value As Integer)
        value = Width
    End Set
End Property
Public Property Area As Integer
    Get
        Return _AreaInteger
    End Get
    Set(value As Integer)
        value = Area
    End Set
End Property
Public Property Name As String
    Get
        Return _CustomerNameString
    End Get
    Set(value As String)
        value = Name
    End Set
End Property
Public Property Price As Integer
    Get
        Return _PriceInteger
    End Get
    Set(value As Integer)
        value = Price
    End Set
End Property
Public Property TotalCost As Integer
    Get
        Return _TotalCostInteger
    End Get
    Set(value As Integer)
        value = TotalCost
    End Set
End Property
Public Sub CalculateArea()
    _AreaInteger = _LengthInteger * _WidthInteger
End Sub
Overridable Sub CalculateCost()
    Const CARPET_Integer As Integer = 10
    Const LAMINATE_Integer As Integer = 20
    Const CERAMIC_Integer As Integer = 25
    Const Hardwood_integer As Integer = 30
    If Price = 0 Then
        _TotalCostInteger = _AreaInteger * CARPET_Integer
    ElseIf Price = 1 Then
        _TotalCostInteger = _AreaInteger * LAMINATE_Integer
    ElseIf Price = 2 Then
        _TotalCostInteger = _AreaInteger * CERAMIC_Integer
    ElseIf Price = 3 Then
        _TotalCostInteger = _AreaInteger * Hardwood_integer
    End If
End Sub
End Class

然后，我将总费用称为：

FlooringObject = New FlooringClass(CInt(LengthTextBox.Text),     CInt(WidthTextBox.Text), NameTextBox.Text, FloorComboBox.SelectedIndex)
CostLabel.Visible = True
CostLabel.Text = (FlooringObject.TotalCost).ToString("C")

等于_TotalCostInteger的标签保持为零，请帮助。

还背负着这个：
如何在不执行事件处理程序（按按钮）的情况下更改标签的文本。 我写的东西只有按一下按钮才能起作用

If FloorComboBox.SelectedIndex <> -1 Then
    If FloorComboBox.SelectedIndex = 0 Then
        PriceLabel.Text = (PriceInteger(0).ToString("C"))
        PriceLabel.Visible = True
    ElseIf FloorComboBox.SelectedIndex = 1 Then
        PriceLabel.Text = PriceInteger(1).ToString("C")
        PriceLabel.Visible = True
    ElseIf FloorComboBox.SelectedIndex = 2 Then
        PriceLabel.Text = PriceInteger(2).ToString("C")
        PriceLabel.Visible = True
    ElseIf FloorComboBox.SelectedIndex = 3 Then
        PriceLabel.Text = PriceInteger(3).ToString("C")
        PriceLabel.Visible = True
    End If

我想要的是标签文本随选定索引的变化而变化。

Answer 1

您的属性的设置器看起来不正确。 它们不会将值设置为您的成员变量。 而是使用value参数，并将其设置为属性的当前值。 它们应如下所示：

Public Property TotalCost As Integer
    Get
        Return _TotalCostInteger
    End Get
    Set(value As Integer)
        _TotalCostInteger = value
    End Set
End Property

如果不单独使用membervariables，则还可以使用如下的自动实现的属性：

Public Property TotalCost As Integer

对于您的其他问题，我假设您正在使用Windows.Forms？ ComboBox有一个SelectedIndexChanged事件，可用于重新计算值，而不是按钮的Click事件。 看这里 。