Question

由于某种原因，我无法在调用Thread.Join（）时让线程结束。我疯了吗？

Public Sub StartThread()
    _opsthread = New Thread(AddressOf OpsThread)
    _opsthread.IsBackground = True
    _opsthread.Start()
End Sub

Public Sub StopThread()
    _continue = False
    _opsthread.Join()
    'Application Hangs Here
End Sub

Public Sub OpsThread()
    While _continue
        Thread.Sleep(1000)
    End While
End Sub

Answer 1

这是我跑过的测试，略有修改。

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    Button1.Enabled = False
    StartThread()
End Sub

Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
    StopThread()
End Sub

Dim _opsthread As Threading.Thread
Dim _continue As New Threading.AutoResetEvent(False)

Public Sub StartThread()
    _continue.Reset()
    _opsthread = New Threading.Thread(AddressOf OpsThread)
    _opsthread.IsBackground = True
    _opsthread.Start()
End Sub

Public Sub StopThread()
    If IsNothing(_opsthread) Then Exit Sub
    _continue.Set()
    _opsthread.Join()
    'Application Hangs Here
    ' Debug.WriteLine("end")
End Sub

Public Sub OpsThread()
    Dim cont As Boolean = False
    While Not cont
        cont = _continue.WaitOne(1000)
    End While
End Sub

Answer 2

您尚未同步_continue的访问权限。出于这个原因，它可能是由JIT注册的。在阅读之前和写完之后，同步对它的访问（例如使用Thread.MemoryBarrier）。

不同步共享数据始终是一个红旗。是因为程序变得越来越糟糕或是因为大多数人都不能很好地理解规则以确保它是安全的（我当然不这样做 - 所以我不这样做）。

线程没有看到全局布尔值

2 个答案: