在中反转枚举VB.NET版

由于枚举是整型的,因此没有通用的方法来完成此操作 Not 对整型执行按位运算,这不是您在这里想要的。但是,在您的情况下,您可以简单地编写一个反转方向的方法:

Module OrientationExtensions

    <Extension()>
    Public Function Invert(ByVal orientation As Orientation) As Orientation
        Return -1 * orientation
    End Function

End Module

用法:

Dim orientation As Orientation
orientation = Module1.Orientation.Ascending
orientation = orientation.Invert()

你只需要知道在你的代码中,每一个逆的枚举值是什么。

对于简单的枚举可能有更简单的方法,但是如果值之间存在复杂的关系,那么将其显式化是唯一的方法。

(您必须原谅C风格的伪代码。)

public Orientation invert(Orientation original)
{
    Orientation result;
    switch (original)
    {
        case Orientation.Descending:
            result = Orientation.Ascending;
            break;
        case Orientation.Ascending:
            result = Orientation.Descending;
            break;
        default:
            result = original;
            break;
    }
    return result;
}

可以创建扩展方法:

Imports System.Runtime.CompilerServices

Module OrientationExtensions

  <Extension()>
  Public Function Invert(ByVal orientation As Orientation) As Orientation
    If orientation = Orientation.Ascending Then
      Return Orientation.Descending
    ElseIf orientation = Orientation.Descending Then
      Return Orientation.Ascending
    Else
      Return Orientation.Undefined
    End If
  End Function

End Module

Dim orientation As Orientation = Orientation.Ascending
Dim inverseOrientation As Orientation = orientation.Invert