SortedList.IsSynchronized 属性

定义

获取一个值,该值指示对 SortedList 对象的访问是否同步(线程安全)。Gets a value indicating whether access to a SortedList object is synchronized (thread safe).

public:
 virtual property bool IsSynchronized { bool get(); };
public virtual bool IsSynchronized { get; }
member this.IsSynchronized : bool
Public Overridable ReadOnly Property IsSynchronized As Boolean

属性值

如果对 true 对象的访问是同步的(线程安全),则为 SortedList;否则为 falsetrue if access to the SortedList object is synchronized (thread safe); otherwise, false. 默认值为 falseThe default is false.

实现

示例

下面的代码示例演示如何在整个枚举过程中使用 SyncRoot 属性锁定集合。The following code example shows how to lock a collection using the SyncRoot property during the entire enumeration.

SortedList^ myCollection = gcnew SortedList();
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);
    }
}
SortedList myCollection = new SortedList();
lock(myCollection.SyncRoot)
{
    foreach (object item in myCollection)
    {
        // Insert your code here.
    }
}
Dim myCollection As New SortedList()
SyncLock myCollection.SyncRoot
    For Each item In myCollection
        ' Insert your code here.
    Next item
End SyncLock

检索此属性的值是一个 O(1) 操作。Retrieving the value of this property is an O(1) operation.

下面的代码示例演示如何同步 SortedList 对象、确定 SortedList 是否同步以及使用同步 SortedListThe following code example shows how to synchronize a SortedList object, determine whether a SortedList is synchronized, and use a synchronized SortedList.

#using <system.dll>

using namespace System;
using namespace System::Collections;
int main()
{
   
   // Creates and initializes a new SortedList.
   SortedList^ mySL = gcnew SortedList;
   mySL->Add( 2, "two" );
   mySL->Add( 3, "three" );
   mySL->Add( 1, "one" );
   mySL->Add( (int^)0, "zero" );
   mySL->Add( 4, "four" );
   
   // Creates a synchronized wrapper around the SortedList.
   SortedList^ mySyncdSL = SortedList::Synchronized( mySL );
   
   // Displays the sychronization status of both SortedLists.
   Console::WriteLine( "mySL is {0}.", mySL->IsSynchronized ? (String^)"synchronized" : "not synchronized" );
   Console::WriteLine( "mySyncdSL is {0}.", mySyncdSL->IsSynchronized ? (String^)"synchronized" : "not synchronized" );
}

/*
This code produces the following output.

mySL is not synchronized.
mySyncdSL is synchronized.
*/
using System;
using System.Collections;
public class SamplesSortedList  {

   public static void Main()  {

      // Creates and initializes a new SortedList.
      SortedList mySL = new SortedList();
      mySL.Add( 2, "two" );
      mySL.Add( 3, "three" );
      mySL.Add( 1, "one" );
      mySL.Add( 0, "zero" );
      mySL.Add( 4, "four" );

      // Creates a synchronized wrapper around the SortedList.
      SortedList mySyncdSL = SortedList.Synchronized( mySL );

      // Displays the sychronization status of both SortedLists.
      Console.WriteLine( "mySL is {0}.", mySL.IsSynchronized ? "synchronized" : "not synchronized" );
      Console.WriteLine( "mySyncdSL is {0}.", mySyncdSL.IsSynchronized ? "synchronized" : "not synchronized" );
   }
}
/* 
This code produces the following output.

mySL is not synchronized.
mySyncdSL is synchronized.
*/ 
Imports System.Collections

Public Class SamplesSortedList
    
    
    Public Shared Sub Main()
        
        ' Creates and initializes a new SortedList.
        Dim mySL As New SortedList()
        mySL.Add(2, "two")
        mySL.Add(3, "three")
        mySL.Add(1, "one")
        mySL.Add(0, "zero")
        mySL.Add(4, "four")
        
        ' Creates a synchronized wrapper around the SortedList.
        Dim mySyncdSL As SortedList = SortedList.Synchronized(mySL)
        
        ' Displays the sychronization status of both SortedLists.
        Dim msg As String
        If mySL.IsSynchronized Then
            msg = "synchronized"
        Else
            msg = "not synchronized"
        End If
        Console.WriteLine("mySL is {0}.", msg)
        If mySyncdSL.IsSynchronized Then
            msg = "synchronized"
        Else
            msg = "not synchronized"
        End If
        Console.WriteLine("mySyncdSL is {0}.", msg)        
    End Sub
End Class

' This code produces the following output.
'
' mySL is not synchronized.
' mySyncdSL is synchronized.

注解

若要保证 SortedList 对象的线程安全,必须通过 Synchronized 方法返回的包装完成所有操作。To guarantee the thread safety of a SortedList object, all operations must be done through the wrapper returned by the Synchronized method.

枚举整个集合本质上不是一个线程安全的过程。Enumerating through a collection is intrinsically not a thread-safe procedure. 即使某个集合已同步,其他线程仍可以修改该集合,这会导致枚举数引发异常。Even when a collection is synchronized, other threads can still modify the collection, which causes the enumerator to throw an exception. 若要确保枚举过程中的线程安全性,可以在整个枚举期间锁定集合,或者捕获由其他线程进行的更改所导致的异常。To guarantee thread safety during enumeration, you can either lock the collection during the entire enumeration or catch the exceptions resulting from changes made by other threads.

适用于

另请参阅