SafeWaitHandle SafeWaitHandle SafeWaitHandle SafeWaitHandle Class

Definición

Representa una clase contenedora para un identificador de espera.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
Herencia
Atributos

Ejemplos

En el ejemplo de código siguiente se muestra cómo utilizar la interoperabilidad para crear una exclusión mutua con el SafeWaitHandle clase y no administrado CreateMutex función.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

Comentarios

El SafeWaitHandle clase la usa el System.Threading.WaitHandle clase.The SafeWaitHandle class is used by the System.Threading.WaitHandle class. Es un contenedor para las exclusiones mutuas de Win32 y automático y eventos de restablecimiento manual.It is a wrapper for Win32 mutexes and auto and manual reset events.

Importante

Este tipo implementa la IDisposable interfaz.This type implements the IDisposable interface. Cuando haya terminado de utilizar el tipo, debe deshacerse de él directa o indirectamente.When you have finished using the type, you should dispose of it either directly or indirectly. Para deshacerse del tipo directamente, llame a su Dispose método en un try / catch bloque.To dispose of the type directly, call its Dispose method in a try/catch block. Para deshacerse de él, indirectamente, usar una construcción de lenguaje, como using (en C#) o Using (en Visual Basic).To dispose of it indirectly, use a language construct such as using (in C#) or Using (in Visual Basic). Para obtener más información, vea la sección "Uso de un objeto que implementa IDisposable" en el IDisposable tema de la interfaz.For more information, see the "Using an Object that Implements IDisposable" section in the IDisposable interface topic.

Constructores

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

Inicializa una nueva instancia de la clase SafeWaitHandle.Initializes a new instance of the SafeWaitHandle class.

Propiedades

IsClosed IsClosed IsClosed IsClosed

Obtiene un valor que indica si el identificador está cerrado.Gets a value indicating whether the handle is closed.

(Inherited from SafeHandle)
IsInvalid IsInvalid IsInvalid IsInvalid

Obtiene un valor que indica si el identificador no es válido.Gets a value that indicates whether the handle is invalid.

Métodos

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

Marca el identificador para soltar y liberar recursos.Marks the handle for releasing and freeing resources.

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

Aumenta manualmente el recuento de referencias en instancias de SafeHandle.Manually increments the reference counter on SafeHandle instances.

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

Devuelve el valor del campo handle.Returns the value of the handle field.

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

Disminuye manualmente el recuento de referencias en una instancia de SafeHandle.Manually decrements the reference counter on a SafeHandle instance.

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

Libera todos los recursos que utiliza la clase SafeHandle.Releases all resources used by the SafeHandle class.

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

Libera los recursos no administrados utilizados por la clase SafeHandle que especifica si se va a realizar una operación de desecho normal.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)

Determina si el objeto especificado es igual al objeto actual.Determines whether the specified object is equal to the current object.

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

Sirve como la función hash predeterminada.Serves as the default hash function.

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

Obtiene el Type de la instancia actual.Gets the Type of the current instance.

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

Crea una copia superficial del Object actual.Creates a shallow copy of the current Object.

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

Cuando se invalida en una clase derivada, ejecuta el código necesario para liberar el identificador.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)

Establece el identificador en el identificador preexistente.Sets the handle to the specified pre-existing handle.

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

Marca un identificador para indicar que ya no se utiliza.Marks a handle as no longer used.

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

Devuelve una cadena que representa el objeto actual.Returns a string that represents the current object.

(Inherited from Object)

Campos

handle handle handle handle

Especifica el identificador que se va a ajustar.Specifies the handle to be wrapped.

(Inherited from SafeHandle)

Seguridad

SecurityCriticalAttribute
requiere plena confianza para el llamador inmediato.requires full trust for the immediate caller. Este miembro no se puede usar código de confianza parcial o transparente.This member cannot be used by partially trusted or transparent code.

Se aplica a

Consulte también: