Question

我有一个抽象类

Public MustInherit Class GenericClass

    Public Sub New(Byval x as Integer)
        ' Some code here
    End Sub    

End Class

我将这个类继承到另一个类，如下所示：

Public Class SpecificClass
    Inherits GenericClass

    Public Sub New(Byval x as Integer)
        MyBase.New(x)
    End Sub

End Class

我想添加一个Shared Function，例如magicFunction以这样一种方式，当我使用它时，它应该返回一个SpecificClass类型的对象。我该怎么办？

我想要这样的东西，但VB.NET中不允许这样做

Public MustInherit Class GenericClass

    Public Sub New(Byval x as Integer)
        ' Some code here
    End Sub    

    Public Shared Function magicFunction(Byval y as Integer) as GenericClass
        Dim z as Integer
        ' Some code here that will alter the value of z
        Return New GenericClass(z) ' Not allowed in VB.NET -- MustInherit class cannot have new
    End Sub    

End Class

调用继承magicFunction的{{1}}应该返回SpecificClass这样的对象：

SpecificClass

任何帮助将不胜感激

Answer 1

这可能有所帮助：

Public MustInherit Class GenericClass(Of T As {GenericClass(Of T)})

    Public Sub New(ByVal x As Integer)
        ' Some code here
    End Sub

    Public Shared Function magicFunction(ByVal y As Integer) As GenericClass(Of T)
        Dim z As Integer
        ' Some code here that will alter the value of z
        Return Activator.CreateInstance(GetType(T), z)
    End Function

End Class

Public Class SpecificClass1
    Inherits GenericClass(Of SpecificClass1)

    Public Sub New(ByVal x As Integer)
        MyBase.New(x)
    End Sub

End Class

Public Class SpecificClass2
    Inherits GenericClass(Of SpecificClass2)

    Public Sub New(ByVal x As Integer)
        MyBase.New(x)
    End Sub

End Class

用法：

    Dim a As SpecificClass1 = SpecificClass1.magicFunction(1)
    Dim b As SpecificClass2 = SpecificClass2.magicFunction(2)

返回Mustinherit类中的self类型 - VB.NET

1 个答案: