SafeWaitHandle SafeWaitHandle SafeWaitHandle SafeWaitHandle Class

Définition

Représente une classe wrapper pour un handle d'attente.Represents a wrapper class for a wait handle.

public ref class SafeWaitHandle sealed : Microsoft::Win32::SafeHandles::SafeHandleZeroOrMinusOneIsInvalid
[System.Security.SecurityCritical]
public sealed class SafeWaitHandle : Microsoft.Win32.SafeHandles.SafeHandleZeroOrMinusOneIsInvalid
type SafeWaitHandle = class
    inherit SafeHandleZeroOrMinusOneIsInvalid
Public NotInheritable Class SafeWaitHandle
Inherits SafeHandleZeroOrMinusOneIsInvalid
Héritage
Attributs

Exemples

L’exemple de code suivant montre comment utiliser l’interopérabilité pour créer un mutex à l’aide de la SafeWaitHandle classe et non managé CreateMutex (fonction).The following code example demonstrates how to use interop to create a mutex using the SafeWaitHandle class and the unmanaged CreateMutex function.

using System;
using Microsoft.Win32.SafeHandles;
using System.Runtime.InteropServices;


class SafeHandlesExample
{

    static void Main()
    {
        UnmanagedMutex uMutex = new UnmanagedMutex("YourCompanyName_SafeHandlesExample_MUTEX");

        try
        {

            uMutex.Create();
            Console.WriteLine("Mutex created. Press Enter to release it.");
            Console.ReadLine();


        }
        catch (Exception e)
        {
            Console.WriteLine(e);
        }
        finally
        {
            uMutex.Release();
            Console.WriteLine("Mutex Released.");
        }

        Console.ReadLine();


    }
}

class UnmanagedMutex 
{


    // Use interop to call the CreateMutex function.
    // For more information about CreateMutex,
    // see the unmanaged MSDN reference library.
    [DllImport("kernel32.dll", CharSet=CharSet.Unicode)]
    static extern SafeWaitHandle CreateMutex(IntPtr lpMutexAttributes, bool bInitialOwner,
    string lpName);


    // Use interop to call the ReleaseMutex function.
    // For more information about ReleaseMutex,
    // see the unmanaged MSDN reference library.
    [DllImport("kernel32.dll")]
    public static extern bool ReleaseMutex(SafeWaitHandle hMutex);



    private SafeWaitHandle handleValue = null;
    private IntPtr mutexAttrValue = IntPtr.Zero;
    private string nameValue = null;

    public UnmanagedMutex(string Name)
    {
        nameValue = Name;
    }


    public void Create()
    {
        if (nameValue == null && nameValue.Length == 0)
        {
            throw new ArgumentNullException("nameValue");
        }

        handleValue = CreateMutex(mutexAttrValue,
                                        true, nameValue);

        // If the handle is invalid,
        // get the last Win32 error 
        // and throw a Win32Exception.
        if (handleValue.IsInvalid)
        {
            Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
        }
    }

    public SafeWaitHandle Handle
    {
        get
        {
            // If the handle is valid,
            // return it.
            if (!handleValue.IsInvalid)
            {
                return handleValue;
            }
            else
            {
                return null;
            }
        }

    }

    public string Name
    {
        get
        {
            return nameValue;
        }

    }


    public void Release()
    {
        ReleaseMutex(handleValue);
    }

}
Imports System
Imports Microsoft.Win32.SafeHandles
Imports System.Runtime.InteropServices

Class SafeHandlesExample


    Shared Sub Main()
        Dim uMutex As New UnmanagedMutex("YourCompanyName_SafeHandlesExample_MUTEX")

        Try

            uMutex.Create()
            Console.WriteLine("Mutex created. Press Enter to release it.")
            Console.ReadLine()


        Catch e As Exception
            Console.WriteLine(e)
        Finally
            uMutex.Release()
            Console.WriteLine("Mutex Released.")
        End Try

        Console.ReadLine()

    End Sub
End Class


Class UnmanagedMutex



    ' Use interop to call the CreateMutex function.
    ' For more information about CreateMutex,
    ' see the unmanaged MSDN reference library.
    <DllImport("kernel32.dll", CharSet:=CharSet.Unicode)> _
    Shared Function CreateMutex(ByVal lpMutexAttributes As IntPtr, ByVal bInitialOwner As Boolean, ByVal lpName As String) As SafeWaitHandle

    End Function



    ' Use interop to call the ReleaseMutex function.
    ' For more information about ReleaseMutex,
    ' see the unmanaged MSDN reference library.
    <DllImport("kernel32.dll")> _
    Public Shared Function ReleaseMutex(ByVal hMutex As SafeWaitHandle) As Boolean

    End Function



    Private handleValue As SafeWaitHandle = Nothing
    Private mutexAttrValue As IntPtr = IntPtr.Zero
    Private nameValue As String = Nothing


    Public Sub New(ByVal Name As String)
        nameValue = Name

    End Sub



    Public Sub Create()
        If nameValue Is Nothing AndAlso nameValue.Length = 0 Then
            Throw New ArgumentNullException("nameValue")
        End If

        handleValue = CreateMutex(mutexAttrValue, True, nameValue)

        ' If the handle is invalid,
        ' get the last Win32 error 
        ' and throw a Win32Exception.
        If handleValue.IsInvalid Then
            Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error())
        End If

    End Sub


    Public ReadOnly Property Handle() As SafeWaitHandle
        Get
            ' If the handle is valid,
            ' return it.
            If Not handleValue.IsInvalid Then
                Return handleValue
            Else
                Return Nothing
            End If
        End Get
    End Property


    Public ReadOnly Property Name() As String
        Get
            Return nameValue
        End Get
    End Property



    Public Sub Release()
        ReleaseMutex(handleValue)

    End Sub
End Class

Remarques

Le SafeWaitHandle classe est utilisée par la System.Threading.WaitHandle classe.The SafeWaitHandle class is used by the System.Threading.WaitHandle class. C’est un wrapper pour les mutex Win32 et auto et événements de réinitialisation manuelle.It is a wrapper for Win32 mutexes and auto and manual reset events.

Important

Ce type implémente le IDisposable interface.This type implements the IDisposable interface. Lorsque vous avez fini d’utiliser le type, vous devez supprimer il directement ou indirectement.When you have finished using the type, you should dispose of it either directly or indirectly. Pour supprimer le type directement, appelez sa Dispose méthode dans un try / catch bloc.To dispose of the type directly, call its Dispose method in a try/catch block. Pour supprimer indirectement, utiliser une construction de langage tel que using (en C#) ou Using (en Visual Basic).To dispose of it indirectly, use a language construct such as using (in C#) or Using (in Visual Basic). Pour plus d’informations, consultez la section « À l’aide un objet qui implémente IDisposable » dans le IDisposable rubrique de l’interface.For more information, see the "Using an Object that Implements IDisposable" section in the IDisposable interface topic.

Constructeurs

SafeWaitHandle(IntPtr, Boolean) SafeWaitHandle(IntPtr, Boolean) SafeWaitHandle(IntPtr, Boolean) SafeWaitHandle(IntPtr, Boolean)

Initialise une nouvelle instance de la classe SafeWaitHandle.Initializes a new instance of the SafeWaitHandle class.

Propriétés

IsClosed IsClosed IsClosed IsClosed

Obtient une valeur indiquant si le handle est fermé.Gets a value indicating whether the handle is closed.

(Inherited from SafeHandle)
IsInvalid IsInvalid IsInvalid IsInvalid

Obtient une valeur qui indique si le handle n'est pas valide.Gets a value that indicates whether the handle is invalid.

Méthodes

Close() Close() Close() Close()

Marque le handle pour libérer des ressources.Marks the handle for releasing and freeing resources.

(Inherited from SafeHandle)
DangerousAddRef(Boolean) DangerousAddRef(Boolean) DangerousAddRef(Boolean) DangerousAddRef(Boolean)

Incrémente manuellement le compteur de références sur les instances de SafeHandle.Manually increments the reference counter on SafeHandle instances.

(Inherited from SafeHandle)
DangerousGetHandle() DangerousGetHandle() DangerousGetHandle() DangerousGetHandle()

Retourne la valeur du champ handle.Returns the value of the handle field.

(Inherited from SafeHandle)
DangerousRelease() DangerousRelease() DangerousRelease() DangerousRelease()

Décrémente manuellement le compteur de références sur une instance de SafeHandle.Manually decrements the reference counter on a SafeHandle instance.

(Inherited from SafeHandle)
Dispose() Dispose() Dispose() Dispose()

Libère toutes les ressources utilisées par la classe SafeHandle.Releases all resources used by the SafeHandle class.

(Inherited from SafeHandle)
Dispose(Boolean) Dispose(Boolean) Dispose(Boolean) Dispose(Boolean)

Libère les ressources non managées utilisées par la classe SafeHandle, en spécifiant s'il faut exécuter une opération de suppression normale.Releases the unmanaged resources used by the SafeHandle class specifying whether to perform a normal dispose operation.

(Inherited from SafeHandle)
Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Détermine si l'objet spécifié est identique à l'objet actuel.Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Fait office de fonction de hachage par défaut.Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

Obtient le Type de l'instance actuelle.Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Crée une copie superficielle de l'objet Object actuel.Creates a shallow copy of the current Object.

(Inherited from Object)
ReleaseHandle() ReleaseHandle() ReleaseHandle() ReleaseHandle()

En cas de substitution dans une classe dérivée, exécute le code nécessaire pour libérer le handle.When overridden in a derived class, executes the code required to free the handle.

(Inherited from SafeHandle)
SetHandle(IntPtr) SetHandle(IntPtr) SetHandle(IntPtr) SetHandle(IntPtr)

Définit le handle au handle préexistant spécifié.Sets the handle to the specified pre-existing handle.

(Inherited from SafeHandle)
SetHandleAsInvalid() SetHandleAsInvalid() SetHandleAsInvalid() SetHandleAsInvalid()

Marque un handle comme n'étant plus utilisé.Marks a handle as no longer used.

(Inherited from SafeHandle)
ToString() ToString() ToString() ToString()

Retourne une chaîne qui représente l'objet actuel.Returns a string that represents the current object.

(Inherited from Object)

Champs

handle handle handle handle

Spécifie le handle à encapsuler.Specifies the handle to be wrapped.

(Inherited from SafeHandle)

Sécurité

SecurityCriticalAttribute
requiert une confiance totale pour l’appelant immédiat.requires full trust for the immediate caller. Ce membre ne peut pas être utilisé par le code de confiance partielle ou transparent.This member cannot be used by partially trusted or transparent code.

S’applique à

Voir aussi