Question

能否在VB中设立一个班级。能够与开关说明中的插图相比较的网络? 例如,我要说的是“oo”类:

Public Class Foo
    Public Bar As String = "test"
End Class

能否实施某些接口或压倒某些平等操作者,以便我能够像现在这样使用Foo?

Dim foo As New Foo()

Select Case "test"
    Case foo
          It worked!
End Select

Answer 1

Yes, you can define implicit conversion operators in the .NET languages that allow the compiler to implicitly convert an instance of your class to another type.

在VB。 NET称为“开发”经营者。请将此定义如下:

Public Class Foo
    Public Bar As String = "test"

    Public Shared Widening Operator CType(ByVal f As Foo) As String
        Return f.Bar
    End Operator
End Class

There is also explicit conversion, which is called the "Narrowing" operator in VB.NET. Just as it sounds, the former conversion can happen automatically, while the latter requires you to explicitly instruct the compiler to perform the conversion. This can prevent some nasty surprises, but also clutters the code.

Answer 2

我认为,根据你的问题,你想看到某个行业的律师协会是否与考试相等。

如果是的话,你可以发挥杠杆作用:

Public Class Foo
    Public Bar As String = "test"

    Public Overrides Function ToString() As String
        Return Bar
    End Function
End Class

您的案情陈述成为:

    Dim foo As New Foo()

    Select Case "test"
        Case foo.ToString
              It worked!
    End Select

You could also implement a default property, but that isn t as clean because a default property are required to have a parameter.

Public Class Foo
    Public Bar As String = "test"

    Default Public ReadOnly Property DefaultProp(JustUseZero As Integer) As String
        Get
            Return Bar
        End Get
    End Property
End Class

which would then be called as:

    Dim foo As New Foo()

    Select Case "test"
        Case foo(0)
              It worked!
    End Select

友情链接