Semaphore.Release Metode

Definisi

Ruang nama:

System.Threading

Rakitan:

netstandard.dll, System.Threading.dll

Keluar dari semaphore.

Overload

Nama	Deskripsi
Release()	Keluar dari semaphore dan mengembalikan jumlah sebelumnya.
Release(Int32)	Keluar dari semaphore berapa kali dan mengembalikan jumlah sebelumnya.

Release()

Sumber:

Semaphore.cs

Keluar dari semaphore dan mengembalikan jumlah sebelumnya.

public:
 int Release();

public int Release();

member this.Release : unit -> int

Public Function Release () As Integer

Mengembalikan

Int32

Hitungan pada semaphore sebelum Release metode dipanggil.

Pengecualian

SemaphoreFullException

Jumlah semaphore sudah pada nilai maksimum.

IOException

Terjadi kesalahan Win32 dengan semaphore bernama.

UnauthorizedAccessException

Semaphore saat ini mewakili semaphore sistem bernama, tetapi pengguna tidak memiliki Modify.

-atau-

Semaphore saat ini mewakili semaphore sistem bernama, tetapi tidak dibuka dengan Modify.

Contoh

Contoh kode berikut membuat semaphore dengan jumlah maksimum tiga dan jumlah awal nol. Contohnya memulai lima utas, yang memblokir menunggu semaphore. Utas Release(Int32) utama menggunakan metode overload untuk meningkatkan jumlah semaphore hingga maksimumnya, memungkinkan tiga utas memasuki semaphore. Setiap utas Thread.Sleep menggunakan metode untuk menunggu satu detik, untuk mensimulasikan pekerjaan, lalu memanggil metode kelebihan beban untuk merilis Release() semaphore.

Setiap kali semaphore dirilis, jumlah semaphore sebelumnya ditampilkan. Pesan konsol melacak penggunaan semaphore. Interval kerja yang disimulasikan sedikit ditingkatkan untuk setiap utas, untuk membuat output lebih mudah dibaca.

using System;
using System.Threading;

public class Example
{
    // A semaphore that simulates a limited resource pool.
    //
    private static Semaphore _pool;

    // A padding interval to make the output more orderly.
    private static int _padding;

    public static void Main()
    {
        // Create a semaphore that can satisfy up to three
        // concurrent requests. Use an initial count of zero,
        // so that the entire semaphore count is initially
        // owned by the main program thread.
        //
        _pool = new Semaphore(initialCount: 0, maximumCount: 3);

        // Create and start five numbered threads. 
        //
        for(int i = 1; i <= 5; i++)
        {
            Thread t = new Thread(new ParameterizedThreadStart(Worker));

            // Start the thread, passing the number.
            //
            t.Start(i);
        }

        // Wait for half a second, to allow all the
        // threads to start and to block on the semaphore.
        //
        Thread.Sleep(500);

        // The main thread starts out holding the entire
        // semaphore count. Calling Release(3) brings the 
        // semaphore count back to its maximum value, and
        // allows the waiting threads to enter the semaphore,
        // up to three at a time.
        //
        Console.WriteLine("Main thread calls Release(3).");
        _pool.Release(releaseCount: 3);

        Console.WriteLine("Main thread exits.");
    }

    private static void Worker(object num)
    {
        // Each worker thread begins by requesting the
        // semaphore.
        Console.WriteLine("Thread {0} begins " +
            "and waits for the semaphore.", num);
        _pool.WaitOne();

        // A padding interval to make the output more orderly.
        int padding = Interlocked.Add(ref _padding, 100);

        Console.WriteLine("Thread {0} enters the semaphore.", num);
        
        // The thread's "work" consists of sleeping for 
        // about a second. Each thread "works" a little 
        // longer, just to make the output more orderly.
        //
        Thread.Sleep(1000 + padding);

        Console.WriteLine("Thread {0} releases the semaphore.", num);
        Console.WriteLine("Thread {0} previous semaphore count: {1}",
            num, _pool.Release());
    }
}

Imports System.Threading

Public Class Example

    ' A semaphore that simulates a limited resource pool.
    '
    Private Shared _pool As Semaphore

    ' A padding interval to make the output more orderly.
    Private Shared _padding As Integer

    <MTAThread> _
    Public Shared Sub Main()
        ' Create a semaphore that can satisfy up to three
        ' concurrent requests. Use an initial count of zero,
        ' so that the entire semaphore count is initially
        ' owned by the main program thread.
        '
        _pool = New Semaphore(0, 3)

        ' Create and start five numbered threads. 
        '
        For i As Integer = 1 To 5
            Dim t As New Thread(New ParameterizedThreadStart(AddressOf Worker))
            'Dim t As New Thread(AddressOf Worker)

            ' Start the thread, passing the number.
            '
            t.Start(i)
        Next i

        ' Wait for half a second, to allow all the
        ' threads to start and to block on the semaphore.
        '
        Thread.Sleep(500)

        ' The main thread starts out holding the entire
        ' semaphore count. Calling Release(3) brings the 
        ' semaphore count back to its maximum value, and
        ' allows the waiting threads to enter the semaphore,
        ' up to three at a time.
        '
        Console.WriteLine("Main thread calls Release(3).")
        _pool.Release(3)

        Console.WriteLine("Main thread exits.")
    End Sub

    Private Shared Sub Worker(ByVal num As Object)
        ' Each worker thread begins by requesting the
        ' semaphore.
        Console.WriteLine("Thread {0} begins " _
            & "and waits for the semaphore.", num)
        _pool.WaitOne()

        ' A padding interval to make the output more orderly.
        Dim padding As Integer = Interlocked.Add(_padding, 100)

        Console.WriteLine("Thread {0} enters the semaphore.", num)
        
        ' The thread's "work" consists of sleeping for 
        ' about a second. Each thread "works" a little 
        ' longer, just to make the output more orderly.
        '
        Thread.Sleep(1000 + padding)

        Console.WriteLine("Thread {0} releases the semaphore.", num)
        Console.WriteLine("Thread {0} previous semaphore count: {1}", _
            num, _
            _pool.Release())
    End Sub
End Class

Keterangan

Utas biasanya menggunakan WaitOne metode untuk memasuki semaphore, dan biasanya menggunakan metode ini kelebihan beban untuk keluar.

SemaphoreFullException Jika dilemparkan oleh Release metode , itu tidak selalu menunjukkan masalah dengan utas panggilan. Kesalahan pemrograman di utas lain mungkin menyebabkan utas tersebut keluar dari semaphore lebih sering daripada yang dimasukkan.

Jika objek saat ini Semaphore mewakili semaphore sistem bernama, pengguna harus memiliki SemaphoreRights.Modify hak dan semaphore harus dibuka dengan SemaphoreRights.Modify hak.

Lihat juga

• Managed Threading
• Semaphore

Release(Int32)

Sumber:

Semaphore.cs

Keluar dari semaphore berapa kali dan mengembalikan jumlah sebelumnya.

public:
 int Release(int releaseCount);

public int Release(int releaseCount);

member this.Release : int -> int

Public Function Release (releaseCount As Integer) As Integer

Parameter

releaseCount

Int32

Berapa kali untuk keluar dari semaphore.

Mengembalikan

Int32

Hitungan pada semaphore sebelum Release metode dipanggil.

Pengecualian

ArgumentOutOfRangeException

releaseCount kurang dari 1.

SemaphoreFullException

Jumlah semaphore sudah pada nilai maksimum.

IOException

Terjadi kesalahan Win32 dengan semaphore bernama.

UnauthorizedAccessException

Semaphore saat ini mewakili semaphore sistem bernama, tetapi pengguna tidak memiliki Modify hak.

-atau-

Semaphore saat ini mewakili semaphore sistem bernama, tetapi tidak dibuka dengan Modify hak.

Contoh

Contoh kode berikut membuat semaphore dengan jumlah maksimum tiga dan jumlah awal nol. Contohnya memulai lima utas, yang memblokir menunggu semaphore. Utas Release(Int32) utama menggunakan metode overload untuk meningkatkan jumlah semaphore hingga maksimumnya, memungkinkan tiga utas memasuki semaphore. Setiap utas Thread.Sleep menggunakan metode untuk menunggu satu detik, untuk mensimulasikan pekerjaan, lalu memanggil metode kelebihan beban untuk merilis Release() semaphore.

Setiap kali semaphore dirilis, jumlah semaphore sebelumnya ditampilkan. Pesan konsol melacak penggunaan semaphore. Interval kerja yang disimulasikan sedikit ditingkatkan untuk setiap utas, untuk membuat output lebih mudah dibaca.

using System;
using System.Threading;

public class Example
{
    // A semaphore that simulates a limited resource pool.
    //
    private static Semaphore _pool;

    // A padding interval to make the output more orderly.
    private static int _padding;

    public static void Main()
    {
        // Create a semaphore that can satisfy up to three
        // concurrent requests. Use an initial count of zero,
        // so that the entire semaphore count is initially
        // owned by the main program thread.
        //
        _pool = new Semaphore(initialCount: 0, maximumCount: 3);

        // Create and start five numbered threads. 
        //
        for(int i = 1; i <= 5; i++)
        {
            Thread t = new Thread(new ParameterizedThreadStart(Worker));

            // Start the thread, passing the number.
            //
            t.Start(i);
        }

        // Wait for half a second, to allow all the
        // threads to start and to block on the semaphore.
        //
        Thread.Sleep(500);

        // The main thread starts out holding the entire
        // semaphore count. Calling Release(3) brings the 
        // semaphore count back to its maximum value, and
        // allows the waiting threads to enter the semaphore,
        // up to three at a time.
        //
        Console.WriteLine("Main thread calls Release(3).");
        _pool.Release(releaseCount: 3);

        Console.WriteLine("Main thread exits.");
    }

    private static void Worker(object num)
    {
        // Each worker thread begins by requesting the
        // semaphore.
        Console.WriteLine("Thread {0} begins " +
            "and waits for the semaphore.", num);
        _pool.WaitOne();

        // A padding interval to make the output more orderly.
        int padding = Interlocked.Add(ref _padding, 100);

        Console.WriteLine("Thread {0} enters the semaphore.", num);
        
        // The thread's "work" consists of sleeping for 
        // about a second. Each thread "works" a little 
        // longer, just to make the output more orderly.
        //
        Thread.Sleep(1000 + padding);

        Console.WriteLine("Thread {0} releases the semaphore.", num);
        Console.WriteLine("Thread {0} previous semaphore count: {1}",
            num, _pool.Release());
    }
}

Imports System.Threading

Public Class Example

    ' A semaphore that simulates a limited resource pool.
    '
    Private Shared _pool As Semaphore

    ' A padding interval to make the output more orderly.
    Private Shared _padding As Integer

    <MTAThread> _
    Public Shared Sub Main()
        ' Create a semaphore that can satisfy up to three
        ' concurrent requests. Use an initial count of zero,
        ' so that the entire semaphore count is initially
        ' owned by the main program thread.
        '
        _pool = New Semaphore(0, 3)

        ' Create and start five numbered threads. 
        '
        For i As Integer = 1 To 5
            Dim t As New Thread(New ParameterizedThreadStart(AddressOf Worker))
            'Dim t As New Thread(AddressOf Worker)

            ' Start the thread, passing the number.
            '
            t.Start(i)
        Next i

        ' Wait for half a second, to allow all the
        ' threads to start and to block on the semaphore.
        '
        Thread.Sleep(500)

        ' The main thread starts out holding the entire
        ' semaphore count. Calling Release(3) brings the 
        ' semaphore count back to its maximum value, and
        ' allows the waiting threads to enter the semaphore,
        ' up to three at a time.
        '
        Console.WriteLine("Main thread calls Release(3).")
        _pool.Release(3)

        Console.WriteLine("Main thread exits.")
    End Sub

    Private Shared Sub Worker(ByVal num As Object)
        ' Each worker thread begins by requesting the
        ' semaphore.
        Console.WriteLine("Thread {0} begins " _
            & "and waits for the semaphore.", num)
        _pool.WaitOne()

        ' A padding interval to make the output more orderly.
        Dim padding As Integer = Interlocked.Add(_padding, 100)

        Console.WriteLine("Thread {0} enters the semaphore.", num)
        
        ' The thread's "work" consists of sleeping for 
        ' about a second. Each thread "works" a little 
        ' longer, just to make the output more orderly.
        '
        Thread.Sleep(1000 + padding)

        Console.WriteLine("Thread {0} releases the semaphore.", num)
        Console.WriteLine("Thread {0} previous semaphore count: {1}", _
            num, _
            _pool.Release())
    End Sub
End Class

Keterangan

Jika utas telah memasuki semaphore beberapa kali, overload metode ini memungkinkan seluruh jumlah semaphore dipulihkan dengan satu panggilan.

SemaphoreFullException Jika dilemparkan oleh Release metode , itu tidak selalu menunjukkan masalah dengan utas panggilan. Kesalahan pemrograman di utas lain mungkin menyebabkan utas tersebut keluar dari semaphore lebih sering daripada yang dimasukkan.

Jika objek saat ini Semaphore mewakili semaphore sistem bernama, pengguna harus memiliki SemaphoreRights.Modify hak dan semaphore harus dibuka dengan SemaphoreRights.Modify hak.

Lihat juga

• Managed Threading
• Semaphore