Thread Synchronized Problem in VB.NET?

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VB

threads

Hello programmers. Sorry for my bad English
I would like to ask about thread. I created a program that uses thread. But I do not understand how to make the thread can sync with one another. Code like below:

Imports System.Threading
Imports System.Runtime.CompilerServices

Public Class EnvironmentTest

    Shared Sub Main()
        Dim objA As New Scrambler(0, 0)
        Dim objB As New Scrambler(0, 2)
        Dim objC As New Scrambler(0, 4)

        objA.ThreadWorker.Start()
        objB.ThreadWorker.Start()
        objC.ThreadWorker.Start()
    End Sub
End Class

Public Class Scrambler
    Public rnd As New Random
    Public _Number As Integer
    Public ThreadWorker As New Thread(AddressOf Random)
    Public _Left As Integer
    Public _Top As Integer
    Sub New(ByVal Left As Integer, ByVal Top As Integer)
        Me._Left = Left
        Me._Top = Top
        'ThreadWorker.IsBackground = True
    End Sub
    <MethodImpl(MethodImplOptions.Synchronized)> _
    Public Sub Random()
        While True
            SyncLock Me
                _Number = rnd.Next(0, 9)
                Console.SetCursorPosition(_Left, _Top)
                Console.Write(_Number)
            End SyncLock
        End While
    End Sub
End Class 

The problem on the Random method that is in the class Scrambler. Every time The Console.Write execute, it moved to the next column (Console should only write in one column because Console.SetCursorPosition always execute before Console.Write executed).

variable rnd.next _Number = (0, 9)
that means the maximum value for the variable _Number is 0 to 9 or one digit. But in the code above, precisely on Console.Write(_Number), _Number printed is 2 digits even more.


Is there someone who can provide solutions?