VB.Net Tutorial/Thread/ThreadStatic

ThreadStatic

Imports System.Threading
public class Test
   Shared Dim obj As MyClass1 = new MyClass1
   public Shared Sub Main
               Dim thread1 As New Thread(AddressOf doSomething)
               Dim thread2 As New Thread(AddressOf doSomething)
               Dim thread3 As New Thread(AddressOf doSomething)
               thread1.Start()
               thread2.Start()
               thread3.Start()
   End Sub
   
   Private Shared Sub doSomething()
           Dim i As Integer
           For i = 1 To 3
               obj.SharedData = i
               obj.threadUniqueID = AppDomain.GetCurrentThreadId()
               Console.WriteLine("ID: " & obj.threadUniqueID & ", I:=" & i & ", SharedData: " & obj.SharedData.ToString())
               Thread.CurrentThread.Sleep(250)
           Next
   End Sub
End class
Public Class MyClass1
       <ThreadStatic()> Public threadUniqueID As Integer
       Public SharedData As Integer = 0
End Class

ID: 2564, I:=1, SharedData: 1
ID: 3196, I:=1, SharedData: 1
ID: 2656, I:=1, SharedData: 1
ID: 2564, I:=2, SharedData: 2
ID: 3196, I:=2, SharedData: 2
ID: 2656, I:=2, SharedData: 2
ID: 2564, I:=3, SharedData: 3
ID: 3196, I:=3, SharedData: 3
ID: 2656, I:=3, SharedData: 3

ThreadStatic field

Imports System.Threading
Public Class SharedByThread
   <ThreadStatic> Private Shared Count As Integer
   Public Shared Sub Main()
   
      Dim secondThread As New thread(AddressOf Thread2Proc)
      secondThread.Start()
      count = 100
      For ctr As Integer = 0 to 10
         Console.WriteLine("The value of count in the main thread is {0}.", count)
         IncrementCounter(200)
      Next
   End Sub
   Public Shared Sub Thread2Proc()
      count = 0
      For ctr As Integer = 0 to 10
         Console.WriteLine("The value of count in the second thread is {0}.", count)
         IncrementCounter(250)
      Next
   End Sub
   Public Shared Sub IncrementCounter(delay As Integer)
      count +=1
      Thread.Sleep(delay)
   End Sub
End Class

The value of count in the second thread is 0.
The value of count in the main thread is 100.
The value of count in the main thread is 101.
The value of count in the second thread is 1.
The value of count in the main thread is 102.
The value of count in the second thread is 2.
The value of count in the main thread is 103.
The value of count in the second thread is 3.
The value of count in the main thread is 104.
The value of count in the second thread is 4.
The value of count in the main thread is 105.
The value of count in the main thread is 106.
The value of count in the second thread is 5.
The value of count in the main thread is 107.
The value of count in the second thread is 6.
The value of count in the main thread is 108.
The value of count in the second thread is 7.
The value of count in the main thread is 109.
The value of count in the second thread is 8.
The value of count in the main thread is 110.
The value of count in the second thread is 9.
The value of count in the second thread is 10.