VB.NET Select Case仅前两个分支生效问题求助

你的代码核心问题出在Select Case的条件写法错误：每个Case里的逗号代表逻辑“或”，而非你预期的区间范围。比如第二个分支Case Is >= 51, Is < 500，实际逻辑是“只要数值≥51 或者 <500就匹配”——所有≥51的数值都会触发这个分支，后续分支永远没机会执行。

修正步骤 #

1. 使用To关键字定义连续数值区间，这是VB.NET中Select Case指定范围的标准方式；
2. 合并两个独立的Select Case逻辑，减少冗余代码；
3. 简化按钮启用状态的判断逻辑，让代码更简洁。

修正后的完整代码 #

Public Class Form1
    Private Sub Exit_Btn_Click(sender As Object, e As EventArgs) Handles AhhFreeAtLastOhGabrielNowDawnsThyReckoningAndThyGoreShallGlistinForTheTemplesOfManCreatureOfSteelMyGratitudeUponTheeForrMyFreedomButTheCrimesThatThyKindHaveCommitedAgienstHumanityAreNotForgottenAndThyPunishmentIsExiting_Btn.Click
        End
    End Sub

    Private Sub Followers_Txt_TextChanged(sender As Object, e As EventArgs) Handles Followers_Txt.TextChanged
        Dim F As Integer
        Dim FollowersOk = Integer.TryParse(Followers_Txt.Text, F)
        
        ' 简化按钮启用逻辑
        Conferm_Btn.Enabled = FollowersOk
        If Not FollowersOk Then
            Followers_Txt.Text = ""
            ' 解析失败时重置显示内容
            Celebrity_Pic.Image = Nothing
            Celebrity_Lbl.Text = ""
            Return
        End If

        ' 合并图片与文本的Select Case逻辑
        Select Case F
            Case < 50
                Celebrity_Pic.Image = My.Resources.stupid_idiot
                Celebrity_Lbl.Text = "Elon"
            Case 51 To 499
                Celebrity_Pic.Image = My.Resources.dream
                Celebrity_Lbl.Text = "Clay"
            Case 501 To 9999
                Celebrity_Pic.Image = My.Resources.Doug_Bowser
                Celebrity_Lbl.Text = "Doug Bowser"
            Case 10001 To 499999
                Celebrity_Pic.Image = My.Resources.mathew_patrick
                Celebrity_Lbl.Text = "Mathew Patrick"
            Case >= 500001
                Celebrity_Pic.Image = My.Resources.Mark_anthony
                Celebrity_Lbl.Text = "Mark Edward Fischbach"
        End Select
    End Sub
End Class

关键修改说明 #

• 将Case Is >= 51, Is < 500改为Case 51 To 499，明确指定连续数值区间；
• 合并两个Select Case，避免重复的条件判断；
• 解析失败时添加重置显示内容的逻辑，优化用户体验；
• 直接用FollowersOk的布尔值赋值给Conferm_Btn.Enabled，简化判断逻辑。

内容的提问来源于stack exchange，提问作者Jack Smith