TimerCallback Delegate (System.Threading)

Imports Microsoft.VisualBasic
Imports System
Imports System.Threading

Public Class TimerExample

    <MTAThread> _
    Shared Sub Main()

        ' Create an event to signal the timeout count threshold in the
        ' timer callback.
        Dim autoEvent As New AutoResetEvent(False)

        Dim statusChecker As New StatusChecker(10)

        ' Create an inferred delegate that invokes methods for the timer.
        Dim tcb As TimerCallback = AddressOf statusChecker.CheckStatus

        ' Create a timer that signals the delegate to invoke
        ' CheckStatus after one second, and every 1/4 second
        ' thereafter.
        Console.WriteLine("{0} Creating timer." & vbCrLf, _
            DateTime.Now.ToString("h:mm:ss.fff"))
        Dim stateTimer As Timer = New Timer(tcb, autoEvent, 1000, 250)

        ' When autoEvent signals, change the period to every 
        ' 1/2 second.
        autoEvent.WaitOne(5000, False)
        stateTimer.Change(0, 500)
        Console.WriteLine(vbCrLf & "Changing period." & vbCrLf)

        ' When autoEvent signals the second time, dispose of 
        ' the timer.
        autoEvent.WaitOne(5000, False)
        stateTimer.Dispose()
        Console.WriteLine(vbCrLf & "Destroying timer.")

    End Sub
End Class

Public Class StatusChecker

    Dim invokeCount, maxCount As Integer 

    Sub New(count As Integer)
        invokeCount  = 0
        maxCount = count
    End Sub

    ' This method is called by the timer delegate.
    Sub CheckStatus(stateInfo As Object)
        Dim autoEvent As AutoResetEvent = _
            DirectCast(stateInfo, AutoResetEvent)
        invokeCount += 1
        Console.WriteLine("{0} Checking status {1,2}.", _
            DateTime.Now.ToString("h:mm:ss.fff"), _
            invokeCount.ToString())

        If invokeCount = maxCount Then
            ' Reset the counter and signal to stop the timer.
            invokeCount  = 0
            autoEvent.Set()
        End If
    End Sub

End Class

using System;
using System.Threading;

class TimerExample
{
    static void Main()
    {
        // Create an event to signal the timeout count threshold in the
        // timer callback.
        AutoResetEvent autoEvent     = new AutoResetEvent(false);

        StatusChecker  statusChecker = new StatusChecker(10);

        // Create an inferred delegate that invokes methods for the timer.
        TimerCallback tcb = statusChecker.CheckStatus;

        // Create a timer that signals the delegate to invoke 
        // CheckStatus after one second, and every 1/4 second 
        // thereafter.
        Console.WriteLine("{0} Creating timer.\n", 
            DateTime.Now.ToString("h:mm:ss.fff"));
        Timer stateTimer = new Timer(tcb, autoEvent, 1000, 250);

        // When autoEvent signals, change the period to every
        // 1/2 second.
        autoEvent.WaitOne(5000, false);
        stateTimer.Change(0, 500);
        Console.WriteLine("\nChanging period.\n");

        // When autoEvent signals the second time, dispose of 
        // the timer.
        autoEvent.WaitOne(5000, false);
        stateTimer.Dispose();
        Console.WriteLine("\nDestroying timer.");
    }
}

class StatusChecker
{
    private int invokeCount;
    private int  maxCount;

    public StatusChecker(int count)
    {
        invokeCount  = 0;
        maxCount = count;
    }

    // This method is called by the timer delegate.
    public void CheckStatus(Object stateInfo)
    {
        AutoResetEvent autoEvent = (AutoResetEvent)stateInfo;
        Console.WriteLine("{0} Checking status {1,2}.", 
            DateTime.Now.ToString("h:mm:ss.fff"), 
            (++invokeCount).ToString());

        if(invokeCount == maxCount)
        {
            // Reset the counter and signal Main.
            invokeCount  = 0;
            autoEvent.Set();
        }
    }
}

using namespace System;
using namespace System::Threading;

ref class StatusChecker
{
private:
    int invokeCount, maxCount;

public:
    StatusChecker(int count)
    {
        invokeCount  = 0;
        maxCount = count;
    }

    // This method is called by the timer delegate.
    void CheckStatus(Object^ stateInfo)
    {
        AutoResetEvent^ autoEvent = dynamic_cast<AutoResetEvent^>(stateInfo);
        Console::WriteLine("{0} Checking status {1,2}.",
            DateTime::Now.ToString("h:mm:ss.fff"),
            (++invokeCount).ToString());

        if (invokeCount == maxCount)
        {
            // Reset the counter and signal Main.
            invokeCount  = 0;
            autoEvent->Set();
        }
    }
};

ref class TimerExample
{
public:
    static void Main()
    {
        // Create an event to signal the timeout count threshold in the
        // timer callback.
        AutoResetEvent^ autoEvent     = gcnew AutoResetEvent(false);

        StatusChecker^  statusChecker = gcnew StatusChecker(10);

        // Create a delegate that invokes methods for the timer.
        TimerCallback^ tcb =
           gcnew TimerCallback(statusChecker, &StatusChecker::CheckStatus);

        // Create a timer that signals the delegate to invoke
        // CheckStatus after one second, and every 1/4 second 
        // thereafter.
        Console::WriteLine("{0} Creating timer.\n",
            DateTime::Now.ToString("h:mm:ss.fff"));
        Timer^ stateTimer = gcnew Timer(tcb, autoEvent, 1000, 250);

        // When autoEvent signals, change the period to every
        // 1/2 second.
        autoEvent->WaitOne(5000, false);
        stateTimer->Change(0, 500);
        Console::WriteLine("\nChanging period.\n");

        // When autoEvent signals the second time, dispose of
        // the timer.
        autoEvent->WaitOne(5000, false);
        stateTimer->~Timer();
        Console::WriteLine("\nDestroying timer.");
    }
};

int main()
{
    TimerExample::Main();
}