Question

我要做的是检查一个值是否与两个数字中的一个匹配（并且很容易添加到要比较的数字）。而不是做一个啰嗦的方式，如：

If Number = 1 Or Number = 2 Then ...

我正在尝试做这样的事情：

If Number In (1,2) Then...

由于In运算符在VB中不可用，我尝试使用以下代码：

Protected SectionID As Integer = HttpContext.Current.Request.QueryString("sectionid")
Protected PageID As Integer = HttpContext.Current.Request.QueryString("pageid")

Protected Sub HotspotsLV_ItemDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.ListViewItemEventArgs) Handles HotspotsLV.ItemDataBound
    Dim SecondLineHolder As HtmlControl = e.Item.FindControl("SecondLineHolder")
    Select Case True
        Case New String("2", "3").Contains(SectionID) : SecondLineHolder.Attributes("style") = "color:#21720B"
        Case New String("8", "12").Contains(PageID) : SecondLineHolder.Attributes("style") = "color:#1B45C2"
    End Select
End Sub

我发现这仅在SectionID为2或PageID为8时才有效。如果SectionID为3或PageID为12，则无效。为什么这是我可以做些什么来试图解决问题？感谢。

Answer 1

经过一段时间的游戏，我找到了一个很好的解决方案：

Select Case True
    Case Array.IndexOf(New Integer() {2, 3}, SectionID) > -1 : SecondLineHolder.Attributes("style") = "color:#21720B"
    Case Array.IndexOf(New Integer() {8, 12}, PageID) > -1 : SecondLineHolder.Attributes("style") = "color:#1B45C2"
End Select

Answer 2

Dim Numbers() As Integer = {1, 2}
If Numbers.Any(Function(i) i = Number) Then

Answer 3

您正在创建String实例而不是数组。尝试将其更改为：

Protected SectionID As Integer = HttpContext.Current.Request.QueryString("sectionid")
Protected PageID As Integer = HttpContext.Current.Request.QueryString("pageid")

Protected Sub HotspotsLV_ItemDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.ListViewItemEventArgs) Handles HotspotsLV.ItemDataBound
    Dim SecondLineHolder As HtmlControl = e.Item.FindControl("SecondLineHolder")
    Dim sections As Integer() = New Integer(){2,3}
    Dim pages As Integer() = New Integer(){8,12}
    Select Case True
        Case sections.Contains(SectionID) : SecondLineHolder.Attributes("style") = "color:#21720B"
        Case pages.Contains(PageID) : SecondLineHolder.Attributes("style") = "color:#1B45C2"
    End Select
End Sub

如果您使用Option Strict On，则会突出显示类型不匹配。在您的初始代码中，New String("2", "3")会创建一个值为222的字符串。

修改

对于3.5之前的.Net版本，Contains方法将不可用。这可以使用IndexOf：

进行模仿

Array.IndexOf(sections, SectionID) > -1
' Equivalent to sections.Contains(SectionID)

VB.NET中SQL IN的等价性

3 个答案:

修改