Stack.Synchronized(Stack) 方法
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。
傳回 Stack 同步處理的 (安全執行緒) 包裝函式。
public:
static System::Collections::Stack ^ Synchronized(System::Collections::Stack ^ stack);
public static System.Collections.Stack Synchronized (System.Collections.Stack stack);
static member Synchronized : System.Collections.Stack -> System.Collections.Stack
Public Shared Function Synchronized (stack As Stack) As Stack
參數
傳回
在 Stack 周圍的同步包裝函式。
例外狀況
stack
為 null
。
範例
下列範例示範如何同步處理 、判斷 是否已Stack同步Stack處理 ,以及使用同步Stack處理。
#using <system.dll>
using namespace System;
using namespace System::Collections;
int main()
{
// Creates and initializes a new Stack.
Stack^ myStack = gcnew Stack;
myStack->Push( "The" );
myStack->Push( "quick" );
myStack->Push( "brown" );
myStack->Push( "fox" );
// Creates a synchronized wrapper around the Stack.
Stack^ mySyncdStack = Stack::Synchronized( myStack );
// Displays the sychronization status of both Stacks.
Console::WriteLine( "myStack is {0}.", myStack->IsSynchronized ? (String^)"synchronized" : "not synchronized" );
Console::WriteLine( "mySyncdStack is {0}.", mySyncdStack->IsSynchronized ? (String^)"synchronized" : "not synchronized" );
}
/*
This code produces the following output.
myStack is not synchronized.
mySyncdStack is synchronized.
*/
using System;
using System.Collections;
public class SamplesStack
{
public static void Main()
{
// Creates and initializes a new Stack.
Stack myStack = new Stack();
myStack.Push("The");
myStack.Push("quick");
myStack.Push("brown");
myStack.Push("fox");
// Creates a synchronized wrapper around the Stack.
Stack mySyncdStack = Stack.Synchronized(myStack);
// Displays the sychronization status of both Stacks.
Console.WriteLine("myStack is {0}.",
myStack.IsSynchronized ? "synchronized" : "not synchronized");
Console.WriteLine("mySyncdStack is {0}.",
mySyncdStack.IsSynchronized ? "synchronized" : "not synchronized");
}
}
/*
This code produces the following output.
myStack is not synchronized.
mySyncdStack is synchronized.
*/
Imports System.Collections
Public Class SamplesStack
Public Shared Sub Main()
' Creates and initializes a new Stack.
Dim myStack As New Stack()
myStack.Push("The")
myStack.Push("quick")
myStack.Push("brown")
myStack.Push("fox")
' Creates a synchronized wrapper around the Stack.
Dim mySyncdStack As Stack = Stack.Synchronized(myStack)
' Displays the sychronization status of both Stacks.
Dim msg As String
If myStack.IsSynchronized Then
msg = "synchronized"
Else
msg = "not synchronized"
End If
Console.WriteLine("myStack is {0}.", msg)
If mySyncdStack.IsSynchronized Then
msg = "synchronized"
Else
msg = "not synchronized"
End If
Console.WriteLine("mySyncdStack is {0}.", msg)
End Sub
End Class
' This code produces the following output.
'
' myStack is not synchronized.
' mySyncdStack is synchronized.
備註
若要保證的 Stack線程安全,所有作業都必須透過這個包裝函式來完成。
透過集合進行列舉在本質上並非安全執行緒程序。 即使集合經過同步化,其他的執行緒仍可修改該集合,使列舉值擲回例外狀況。 若要保證列舉過程的執行緒安全,您可以在整個列舉過程中鎖定集合,或攔截由其他執行緒的變更所造成的例外狀況。
下列程式代碼範例示範如何在整個列舉期間使用 SyncRoot 鎖定 集合。
Stack^ myCollection = gcnew Stack();
bool lockTaken = false;
try
{
Monitor::Enter(myCollection->SyncRoot, lockTaken);
for each (Object^ item in myCollection);
{
// Insert your code here.
}
}
finally
{
if (lockTaken)
{
Monitor::Exit(myCollection->SyncRoot);
}
}
Stack myCollection = new Stack();
lock (myCollection.SyncRoot)
{
foreach (object item in myCollection)
{
// Insert your code here.
}
}
Dim myCollection As New Stack()
SyncLock myCollection.SyncRoot
For Each item As Object In myCollection
' Insert your code here.
Next item
End SyncLock
這個方法是 O(1)
作業。