SafeWaitHandle 類別
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
代表等候控制代碼的包裝函式類別。
public ref class SafeWaitHandle sealed : System::Runtime::InteropServices::SafeHandle
public ref class SafeWaitHandle sealed : Microsoft::Win32::SafeHandles::SafeHandleZeroOrMinusOneIsInvalid
[System.Security.SecurityCritical]
public sealed class SafeWaitHandle : System.Runtime.InteropServices.SafeHandle
public sealed class SafeWaitHandle : Microsoft.Win32.SafeHandles.SafeHandleZeroOrMinusOneIsInvalid
[System.Security.SecurityCritical]
public sealed class SafeWaitHandle : Microsoft.Win32.SafeHandles.SafeHandleZeroOrMinusOneIsInvalid
[<System.Security.SecurityCritical>]
type SafeWaitHandle = class
inherit SafeHandle
type SafeWaitHandle = class
inherit SafeHandleZeroOrMinusOneIsInvalid
[<System.Security.SecurityCritical>]
type SafeWaitHandle = class
inherit SafeHandleZeroOrMinusOneIsInvalid
Public NotInheritable Class SafeWaitHandle
Inherits SafeHandle
Public NotInheritable Class SafeWaitHandle
Inherits SafeHandleZeroOrMinusOneIsInvalid
- 繼承
- 繼承
- 屬性
範例
下列程式代碼範例示範如何使用 Interop,使用 SafeWaitHandle 類別和 Unmanaged 函 CreateMutex
式建立 Mutex。
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 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
備註
類別 SafeWaitHandle 會使用 System.Threading.WaitHandle 類別。 它是 Win32 Mutex 和自動和手動重設事件的包裝函式。
重要
此型別代表 IDisposable 介面。 當您完成使用型別時,您應該直接或間接處置它。 若要直接處置型別,請呼叫其 try
/catch
區塊中的 Dispose 方法。 若要間接處置它,請使用語言建構函式,例如 using
(在 C# 中) 或 Using
(在 Visual Basic 中)。 如需詳細資訊,請參閱 IDisposable 介面文章中的<使用實作 IDisposable 的物件>一節。
建構函式
SafeWaitHandle() |
建立 SafeWaitHandle。 |
SafeWaitHandle(IntPtr, Boolean) |
初始化 SafeWaitHandle 類別的新執行個體。 |
欄位
handle |
指定要包裝的控制代碼。 (繼承來源 SafeHandle) |
屬性
IsClosed |
取得值,指出控制代碼是否已關閉。 (繼承來源 SafeHandle) |
IsInvalid |
取得值,表示控制代碼是否無效。 |
IsInvalid |
取得值,表示控制代碼是否無效。 (繼承來源 SafeHandleZeroOrMinusOneIsInvalid) |
方法
Close() |
標記要釋出和釋放資源的控制代碼。 (繼承來源 SafeHandle) |
DangerousAddRef(Boolean) |
手動遞增 SafeHandle 執行個體上的參考計數器。 (繼承來源 SafeHandle) |
DangerousGetHandle() |
傳回 handle 欄位的值。 (繼承來源 SafeHandle) |
DangerousRelease() |
手動遞減 SafeHandle 執行個體上的參考計數器。 (繼承來源 SafeHandle) |
Dispose() |
釋放 SafeHandle 類別所使用的所有資源。 (繼承來源 SafeHandle) |
Dispose(Boolean) |
釋放 SafeHandle 類別所使用的 Unmanaged 資源,指定是否要執行一般處置作業。 (繼承來源 SafeHandle) |
Equals(Object) |
判斷指定的物件是否等於目前的物件。 (繼承來源 Object) |
GetHashCode() |
做為預設雜湊函式。 (繼承來源 Object) |
GetType() |
取得目前執行個體的 Type。 (繼承來源 Object) |
MemberwiseClone() |
建立目前 Object 的淺層複製。 (繼承來源 Object) |
ReleaseHandle() |
在衍生類別中覆寫時,執行釋放控制代碼所需的程式碼。 (繼承來源 SafeHandle) |
SetHandle(IntPtr) |
將控制代碼設定為指定的既有控制代碼。 (繼承來源 SafeHandle) |
SetHandleAsInvalid() |
將控制代碼標記為不再使用。 (繼承來源 SafeHandle) |
ToString() |
傳回代表目前物件的字串。 (繼承來源 Object) |