CollectionBase.ICollection.IsSynchronized 属性

定义

获取一个值,该值指示是否同步对 CollectionBase 的访问(线程安全)。Gets a value indicating whether access to the CollectionBase is synchronized (thread safe).

property bool System::Collections::ICollection::IsSynchronized { bool get(); };
bool System.Collections.ICollection.IsSynchronized { get; }
 ReadOnly Property IsSynchronized As Boolean Implements ICollection.IsSynchronized

属性值

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

实现

注解

CollectionBase 实例未同步。A CollectionBase instance is not synchronized. 派生类可以使用 SyncRoot 属性提供 CollectionBase 的同步版本。Derived classes can provide a synchronized version of the CollectionBase using the SyncRoot property.

枚举集合本质上不是线程安全的过程。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.

下面的代码示例演示如何使用 SyncRoot 在整个枚举过程中锁定集合:The following code example shows how to lock the collection using the SyncRoot during the entire enumeration:

// Get the ICollection interface from the CollectionBase
// derived class.
ICollection^ myCollection = myCollectionBase;
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);
    }
}
// Get the ICollection interface from the CollectionBase
// derived class.
ICollection myCollection = myCollectionBase;
lock(myCollection.SyncRoot)
{
    foreach (object item in myCollection)
    {
        // Insert your code here.
    }
}
' Get the ICollection interface from the CollectionBase
' derived class.
Dim myCollection As ICollection = myCollectionBase
SyncLock myCollection.SyncRoot
    For Each item As Object 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.

适用于

另请参阅