如何在 Class 下的 VB.NET 中编码此 "Public Property Flow(NumCommodities - 1) As Double"？

Question

我正在尝试在 class 下对这个 "Public Property Flow(NumCommodities - 1) As Double" 进行编码，但显然它需要额外的编码。

所以我需要这个属性因为我需要根据这段代码跟踪值：

For t As Integer = 0 To MyProblem.Arcs.Count-1
    For k = 0 To MyProblem.NumCommodities-1
        Dim i As Integer = MyProblem.Arcs(t).Tail
        Dim j As Integer = MyProblem.Arcs(t).Head
        Dim akey As String = "x(" & i & "," & j & "," & k & ")“
        Dim aid As Integer = solver.GetIndexFromKey(akey)
        MyProblem.Arcs(t).Flow(k) = solver.GetValue(aid).ToDouble
    Next
Next

OBS：我已经在我的问题下声明了这个 Class

Public Class MyProblem
    Public NumCommodities

Answer 1

您不能声明大小可变的数组。相反，您必须声明然后初始化它。

Public Property Flow As Double() = New Double(NumCommodities - 1) {}

请注意，如果 NumCommodities - 1 为负数或 NumCommodities 尚未实例化，这将失败。

由于您的问题没有提供很多关于问题的见解，您可能还试图声明一个属性来访问数组的一个项目。以下是您将如何实现这样的事情：

Private _Flow As Double() = New Double() {}
Public Property Flow(ByVal NumCommodities As Int32) As Double
    Get
        Return _Flow(NumCommodities - 1)
    End Get
    Set(value As Double)
        _Flow(NumCommodities - 1) = value
    End Set
End Property

如何在 Class 下的 VB.NET 中编码此 "Public Property Flow(NumCommodities - 1) As Double"？

How do I code this "Public Property Flow(NumCommodities - 1) As Double" in a VB.NET under a Class?

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