TimerCallback TimerCallback TimerCallback TimerCallback Delegate

定義

Timer からの呼び出しを処理するメソッドを表します。Represents the method that handles calls from a Timer.

public delegate void TimerCallback(System::Object ^ state);
[System.Runtime.InteropServices.ComVisible(true)]
public delegate void TimerCallback(object state);
type TimerCallback = delegate of obj -> unit
Public Delegate Sub TimerCallback(state As Object)

パラメーター

state
Object Object Object Object

このデリゲートで呼び出されたメソッドに関連するアプリケーション固有の情報を格納するオブジェクト、または nullAn object containing application-specific information relevant to the method invoked by this delegate, or null.

継承
TimerCallbackTimerCallbackTimerCallbackTimerCallback
属性

次のコード例で使用されるデリゲートを作成する方法を示しています、Timerクラス。The following code example shows how to create the delegate used with the Timer class.

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:h:mm:ss.fff} Checking status {1,2}.",
                           DateTime::Now, ++invokeCount);

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

ref class TimerExample
{
public:
    static void Main()
    {
        // Create an AutoResetEvent to signal the timeout threshold in the
        // timer callback has been reached.
        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 invokes CheckStatus after one second, 
        // and every 1/4 second thereafter.
        Console::WriteLine("{0:h:mm:ss.fff} Creating timer.\n",
                           DateTime::Now);
        Timer^ stateTimer = gcnew Timer(tcb, autoEvent, 1000, 250);

        // When autoEvent signals, change the period to every half second.
        autoEvent->WaitOne(5000, false);
        stateTimer->Change(0, 500);
        Console::WriteLine("\nChanging period to .5 seconds.\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();
}
// The example displays output like the following:
//       11:59:54.202 Creating timer.
//       
//       11:59:55.217 Checking status  1.
//       11:59:55.466 Checking status  2.
//       11:59:55.716 Checking status  3.
//       11:59:55.968 Checking status  4.
//       11:59:56.218 Checking status  5.
//       11:59:56.470 Checking status  6.
//       11:59:56.722 Checking status  7.
//       11:59:56.972 Checking status  8.
//       11:59:57.223 Checking status  9.
//       11:59:57.473 Checking status 10.
//       
//       Changing period to .5 seconds.
//       
//       11:59:57.474 Checking status  1.
//       11:59:57.976 Checking status  2.
//       11:59:58.476 Checking status  3.
//       11:59:58.977 Checking status  4.
//       11:59:59.477 Checking status  5.
//       11:59:59.977 Checking status  6.
//       12:00:00.478 Checking status  7.
//       12:00:00.980 Checking status  8.
//       12:00:01.481 Checking status  9.
//       12:00:01.981 Checking status 10.
//       
//       Destroying timer.
using System;
using System.Threading;

class TimerExample
{
    static void Main()
    {
        // Create an AutoResetEvent to signal the timeout threshold in the
        // timer callback has been reached.
        var autoEvent = new AutoResetEvent(false);
        
        var statusChecker = new StatusChecker(10);

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

        // When autoEvent signals, change the period to every half second.
        autoEvent.WaitOne();
        stateTimer.Change(0, 500);
        Console.WriteLine("\nChanging period to .5 seconds.\n");

        // When autoEvent signals the second time, dispose of the timer.
        autoEvent.WaitOne();
        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 the waiting thread.
            invokeCount = 0;
            autoEvent.Set();
        }
    }
}
// The example displays output like the following:
//       11:59:54.202 Creating timer.
//       
//       11:59:55.217 Checking status  1.
//       11:59:55.466 Checking status  2.
//       11:59:55.716 Checking status  3.
//       11:59:55.968 Checking status  4.
//       11:59:56.218 Checking status  5.
//       11:59:56.470 Checking status  6.
//       11:59:56.722 Checking status  7.
//       11:59:56.972 Checking status  8.
//       11:59:57.223 Checking status  9.
//       11:59:57.473 Checking status 10.
//       
//       Changing period to .5 seconds.
//       
//       11:59:57.474 Checking status  1.
//       11:59:57.976 Checking status  2.
//       11:59:58.476 Checking status  3.
//       11:59:58.977 Checking status  4.
//       11:59:59.477 Checking status  5.
//       11:59:59.977 Checking status  6.
//       12:00:00.478 Checking status  7.
//       12:00:00.980 Checking status  8.
//       12:00:01.481 Checking status  9.
//       12:00:01.981 Checking status 10.
//       
//       Destroying timer.
Imports System.Threading

Public Module Example
    Public Sub Main()
        ' Use an AutoResetEvent to signal the timeout threshold in the
        ' timer callback has been reached.
        Dim autoEvent As New AutoResetEvent(False)

        Dim statusChecker As New StatusChecker(10)

        ' Create a timer that invokes CheckStatus after one second, 
        ' and every 1/4 second thereafter.
        Console.WriteLine("{0:h:mm:ss.fff} Creating timer." & vbCrLf, 
                          DateTime.Now)
        Dim stateTimer As New Timer(AddressOf statusChecker.CheckStatus, 
                                    autoEvent, 1000, 250)

        ' When autoEvent signals, change the period to every half second.
        autoEvent.WaitOne()
        stateTimer.Change(0, 500)
        Console.WriteLine(vbCrLf & "Changing period to .5 seconds." & vbCrLf)

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

Public Class StatusChecker
    Dim invokeCount, maxCount As Integer 

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

    ' The timer callback method.
    Sub CheckStatus(stateInfo As Object)
        Dim autoEvent As AutoResetEvent = DirectCast(stateInfo, AutoResetEvent)
        invokeCount += 1
        Console.WriteLine("{0:h:mm:ss.fff} Checking status {1,2}.", 
                          DateTime.Now, invokeCount)
        If invokeCount = maxCount Then
            ' Reset the counter and signal the waiting thread.
            invokeCount = 0
            autoEvent.Set()
        End If
    End Sub
End Class
' The example displays output like the following:
'       11:59:54.202 Creating timer.
'       
'       11:59:55.217 Checking status  1.
'       11:59:55.466 Checking status  2.
'       11:59:55.716 Checking status  3.
'       11:59:55.968 Checking status  4.
'       11:59:56.218 Checking status  5.
'       11:59:56.470 Checking status  6.
'       11:59:56.722 Checking status  7.
'       11:59:56.972 Checking status  8.
'       11:59:57.223 Checking status  9.
'       11:59:57.473 Checking status 10.
'       
'       Changing period to .5 seconds.
'       
'       11:59:57.474 Checking status  1.
'       11:59:57.976 Checking status  2.
'       11:59:58.476 Checking status  3.
'       11:59:58.977 Checking status  4.
'       11:59:59.477 Checking status  5.
'       11:59:59.977 Checking status  6.
'       12:00:00.478 Checking status  7.
'       12:00:00.980 Checking status  8.
'       12:00:01.481 Checking status  9.
'       12:00:01.981 Checking status 10.
'       
'       Destroying timer.

注釈

使用して、TimerCallbackによって呼び出されるメソッドを指定するデリゲート、Timerします。Use a TimerCallback delegate to specify the method that is called by a Timer. このメソッドは、タイマー; を作成したスレッドで実行しません。システムによって提供される、別のスレッド プールのスレッドを実行します。This method does not execute in the thread that created the timer; it executes in a separate thread pool thread that is provided by the system. TimerCallbackデリゲートは、開始時間が経過後に 1 回のメソッドを呼び出すし、タイマー間隔まであたり 1 回呼び出すことは引き続き、Disposeメソッドが呼び出されるまで、または、Timer.Change間隔の値を持つメソッドが呼び出されるInfiniteします。The TimerCallback delegate invokes the method once after the start time elapses, and continues to invoke it once per timer interval until the Dispose method is called, or until the Timer.Change method is called with the interval value Infinite.

注意

コールバックが後に発生することが、Dispose()メソッドのオーバー ロードが呼び出されたため、タイマー キューのスレッド プールのスレッドでコールバックを実行します。Callbacks can occur after the Dispose() method overload has been called, because the timer queues callbacks for execution by thread pool threads. 使用することができます、Dispose(WaitHandle)メソッドのオーバー ロードは、すべてのコールバックが完了するまで待機します。You can use the Dispose(WaitHandle) method overload to wait until all callbacks have completed.

タイマーが構築され、変更することはできません、タイマーのデリゲートを指定します。The timer delegate is specified when the timer is constructed, and cannot be changed. 開始時刻、Timerで渡される、dueTimeのパラメーター、Timerコンス トラクター、および期間がで渡される、periodパラメーター。The start time for a Timer is passed in the dueTime parameter of the Timer constructors, and the period is passed in the period parameter. 作成と使用を示す例については、TimerCallbackデリゲートは、「System.Threading.Timerします。For an example that demonstrates creating and using a TimerCallback delegate, see System.Threading.Timer.

拡張メソッド

GetMethodInfo(Delegate) GetMethodInfo(Delegate) GetMethodInfo(Delegate) GetMethodInfo(Delegate)

指定したデリゲートによって表されるメソッドを表すオブジェクトを取得します。Gets an object that represents the method represented by the specified delegate.

適用対象

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