VB.NET ช่วยดู Code ให้หน่อยครับ คือผมมีปัญหากับ Thread ....

 Shared x As Integer = 0
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim ctThread As Thread = New Thread(AddressOf r)
        ctThread.IsBackground = True
        ctThread.Start()
    End Sub
    Sub r()
        Dim s As New a
        x += 1
        count()
        s.str()
    End Sub
    Class a
        Sub str()
            Dim ctThread As Threading.Thread = New Threading.Thread(AddressOf d)
            ctThread.Start()
        End Sub
        Sub d()
            Thread.Sleep(2000)
            x -= 1
            Form1.count()
        End Sub
    End Class
    Private Delegate Sub UpdateTextBox(ByVal recvData As String)
    Sub count()
        If Label1.InvokeRequired Then
            Dim d As New UpdateTextBox(AddressOf count)
            Me.BeginInvoke(d, x.ToString)
        Else
            Label1.Text = x
        End If
    End Sub