Timer Constructor

Initializes a new instance of the Timer class.

Overload List

Initializes a new instance of the Timer class, using a 32-bit signed integer to specify the time interval.

Supported by the .NET Compact Framework.

[Visual Basic] Public Sub New(TimerCallback, Object, Integer, Integer)

[C#] public Timer(TimerCallback, object, int, int);

[C++] public: Timer(TimerCallback*, Object*, int, int);

[JScript] public function Timer(TimerCallback, Object, int, int);

Initializes a new instance of the Timer class, using 64-bit signed integers to measure time intervals.

Supported by the .NET Compact Framework.

[Visual Basic] Public Sub New(TimerCallback, Object, Long, Long)

[C#] public Timer(TimerCallback, object, long, long);

[C++] public: Timer(TimerCallback*, Object*, __int64, __int64);

[JScript] public function Timer(TimerCallback, Object, long, long);

Initializes a new instance of the Timer class, using TimeSpan values to measure time intervals.

Supported by the .NET Compact Framework.

[Visual Basic] Public Sub New(TimerCallback, Object, TimeSpan, TimeSpan)

[C#] public Timer(TimerCallback, object, TimeSpan, TimeSpan);

[C++] public: Timer(TimerCallback*, Object*, TimeSpan, TimeSpan);

[JScript] public function Timer(TimerCallback, Object, TimeSpan, TimeSpan);

Initializes a new instance of the Timer class, using 32-bit unsigned integers to measure time intervals. This constructor is not CLS-compliant.

Supported by the .NET Compact Framework.

[Visual Basic] Public Sub New(TimerCallback, Object, UInt32, UInt32)

[C#] public Timer(TimerCallback, object, uint, uint);

[C++] public: Timer(TimerCallback*, Object*, unsigned int, unsigned int);

[JScript] public function Timer(TimerCallback, Object, UInt32, UInt32);

Example

[Visual Basic, C#, C++] The following code example shows how to create a TimerCallback delegate and initialize a new instance of the Timer class.

[Visual Basic, C#, C++] Note   This example shows how to use one of the overloaded versions of the Timer constructor. For other examples that might be available, see the individual overload topics.

[Visual Basic] 
Imports Microsoft.VisualBasic
Imports System
Imports System.Threading

Public Class TimerExample

    Shared Sub Main()
    
        Dim autoEvent As New AutoResetEvent(False)
        Dim statusChecker As New StatusChecker(10)

        ' Create the delegate that invokes methods for the timer.
        Dim timerDelegate As TimerCallback = _
            AddressOf statusChecker.CheckStatus

        Dim delayTime As New TimeSpan(0, 0, 1)
        Dim intervalTime As New TimeSpan(0, 0, 0, 0, 250)

        ' 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( _
            timerDelegate, autoEvent, delayTime, intervalTime)

        ' When autoEvent signals, change the period to every 
        ' 1/2 second.
        autoEvent.WaitOne(5000, False)
        stateTimer.Change( _
            new TimeSpan(0), intervalTime.Add(intervalTime))
        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

[C#] 
using System;
using System.Threading;

class TimerExample
{
    static void Main()
    {
        AutoResetEvent autoEvent     = new AutoResetEvent(false);
        StatusChecker  statusChecker = new StatusChecker(10);

        // Create the delegate that invokes methods for the timer.
        TimerCallback timerDelegate = 
            new TimerCallback(statusChecker.CheckStatus);

        TimeSpan delayTime = new TimeSpan(0, 0, 1);
        TimeSpan intervalTime = new TimeSpan(0, 0, 0, 0, 250);

        // 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(
            timerDelegate, autoEvent, delayTime, intervalTime);

        // When autoEvent signals, change the period to every 
        // 1/2 second.
        autoEvent.WaitOne(5000, false);
        stateTimer.Change(new TimeSpan(0), 
            intervalTime + intervalTime);
        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
{
    int invokeCount, 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();
        }
    }
}

[C++] 
#using <mscorlib.dll>
using namespace System;
using namespace System::Threading;

__gc class StatusChecker
{
    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(S"{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();
        }
    }
};

void main()
{
    AutoResetEvent* autoEvent     = new AutoResetEvent(false);
    StatusChecker*  statusChecker = new StatusChecker(10);

    // Create the delegate that invokes methods for the timer.
    TimerCallback* timerDelegate = new TimerCallback(
        statusChecker, &StatusChecker::CheckStatus);

    TimeSpan delayTime = TimeSpan(0, 0, 1);
    TimeSpan intervalTime = TimeSpan(0, 0, 0, 0, 250);

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

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

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

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button in the upper-left corner of the page.

See Also

Timer Class | Timer Members | System.Threading Namespace