Question

我正在使用Visual Basic编写一个wpf应用程序，我想使用继承函数来创建我的自定义类。我做了一个虚拟项目，只是为了让每个人都明白我的问题。

我想从父类继承属性到我的子类。请注意孩子班。我的问题在于编写代码的方式;

- 当我想在代码后面的mainwindow中调用子类时，我无法为子类的所有固有属性赋值，它只允许我为子类中的新属性赋值如下图所示。

Dim ChildClass As New ChildClass(var5, var6)'<---Unable to assing values to the rest of the inherited properties

- 在子类中，我无法将字段分配给固有属性，在那里你会看到这个奇怪的

MyBase.New(1, 1, 1, 1)

这基本上阻止我控制固有属性的值。

然而，正如您在代码后面的主窗口中看到的那样，我能够阅读和使用子类的所有6个属性（固有的和新的），但是对于固有的属性，它们具有不理想的值。

当我从代码后面的主窗口调用子类时，我希望能够为所有6个属性赋值。

我猜所有的构造函数定义都与这个问题有关，所以如果你可以尝试运行我的程序并提出一个解决方案就会很棒！

我的MainWindow XAML文件：

<Window x:Class="MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="InheritClassExample" Height="350" Width="525">
    <StackPanel>
        <TextBox Name="val1" Text="1"></TextBox>
        <TextBox Name="val2" Text="2"></TextBox>
        <TextBox Name="val3" Text="3"></TextBox>
        <TextBox Name="val4" Text="4"></TextBox>
        <TextBox Name="val5" Text="5"></TextBox>
        <TextBox Name="val6" Text="6"></TextBox>
        <Button Margin="50" Click="Button_Click">GO!</Button>
        <WrapPanel Margin="10">
            <TextBox Name="ParentClassBox" Width="auto"></TextBox>
            <TextBox Name="ChildClassBox" Width="auto"></TextBox>
        </WrapPanel>
    </StackPanel>

</Window>

我的MainWindow背后的代码：

 Imports DummyInheritExample.Utilities

Class MainWindow

    Private Sub Button_Click(sender As Object, e As RoutedEventArgs)
        'assign the values from my input window to varriables withing this sub
        Dim var1 As Double = val1.Text
        Dim var2 As Double = val2.Text
        Dim var3 As Double = val3.Text
        Dim var4 As Double = val4.Text
        Dim var5 As Double = val5.Text
        Dim var6 As Double = val6.Text

        'calling the parent class

        Dim parentClass As New ParentClass(var1, var2, var3, var4)
        ParentClassBox.Text = "The numerical valeus in the ParentClass are :" + parentClass.field1.ToString + parentClass.field2.ToString + parentClass.field3.ToString + parentClass.field4.ToString

        Dim ChildClass As New ChildClass(var5, var6)'<---Unable to assing values to the rest of the inherited properties
        ChildClassBox.Text = "The numerical valeus in the ChildClass are :" + ChildClass.field1.ToString + ChildClass.field2.ToString + ChildClass.field3.ToString + ChildClass.field4.ToString + ChildClass.field5.ToString + ChildClass.field6.ToString

    End Sub
End Class

我父类的代码：

Namespace Utilities
    Public Class ParentClass

        Sub New(_field1 As Double, _field2 As Double, _field3 As Double, _field4 As Double)
            field1 = _field1
            field2 = _field2
            field3 = _field3
            field4 = _field4
        End Sub


        Private _field1 As Double

        Public Property field1() As Double
            Get
                Return _field1
            End Get
            Set(ByVal value As Double)
                _field1 = value
            End Set
        End Property

        Private _field2 As Double
        Public Property field2() As Double
            Get
                Return _field2
            End Get
            Set(ByVal value As Double)
                _field2 = value
            End Set
        End Property

        Private _field3 As Double
        Public Property field3() As Double
            Get
                Return _field3
            End Get
            Set(ByVal value As Double)
                _field3 = value
            End Set
        End Property

        Private _field4 As Double
        Public Property field4() As Double
            Get
                Return _field4
            End Get
            Set(ByVal value As Double)
                _field4 = value
            End Set
        End Property


    End Class
End Namespace

我的儿童班的代码：

Namespace Utilities
    Public Class ChildClass
        Inherits ParentClass

        Sub New(_field5 As Double, _field6 As Double)
            MyBase.New(1, 1, 1, 1) ' here visual basic asked me to enter this statment
            field5 = _field5
            field6 = _field6
        End Sub


        Private _field5 As Double
        Public Property field5() As Double
            Get
                Return _field5
            End Get
            Set(ByVal value As Double)
                _field5 = value
            End Set
        End Property

        Private _field6 As Double
        Public Property field6() As Double
            Get
                Return _field6
            End Get
            Set(ByVal value As Double)
                _field6 = value
            End Set
        End Property

        Dim test As Double = field1



    End Class
End Namespace

Answer 1

不确定这是不是您的意思 - 在Child类中添加包含所有字段的构造函数。

Sub New(_field1 As Double, _field2 As Double, _field3 As Double, _field4 As Double, _field5 As Double, _field6 As Double)
            MyBase.New(_field1, _field2, _field3, _field4)

Answer 2

是的，谢谢Priya，谢谢你，这是正确的。我解决了我的问题，构造函数现在看起来像这样：

Sub New(ByVal _field1 As Double, _field2 As Double, ByVal _field3 As Double, _field4 As Double, ByVal _field5 As Double, _field6 As Double)
    MyBase.New(_field1, _field2, _field3, _field4)
    Me.field5 = _field5
    Me.field6 = _field6

End Sub

使用visual basic

2 个答案: