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SyncRoot 屬性

Gets an object that can be used to synchronize access to the collection.

命名空間：  Microsoft.SqlServer.Dts.Runtime.Enumerators.Item
組件：  Microsoft.SqlServer.ManagedDTS (在 Microsoft.SqlServer.ManagedDTS.dll 中)

語法

'宣告
Public ReadOnly Property SyncRoot As Object
    Get
'用途
Dim instance As ForEachItem
Dim value As Object

value = instance.SyncRoot

public Object SyncRoot { get; }

public:
virtual property Object^ SyncRoot {
    Object^ get () sealed;
}

abstract SyncRoot : Object
override SyncRoot : Object

final function get SyncRoot () : Object

屬性值

型別：System. . :: . .Object
An object that can be used to synchronize access to the collection.

實作

ICollection. . :: . .SyncRoot

備註

Implements ICollection.IsSynchronized. If you are creating a custom collection and deriving from DTSReadOnlyCollectionBase, you can provide your own synchronized version of the collection using the SyncRoot property. The synchronizing code must perform operations on the SyncRoot of the collection, not directly on the collection. This ensures proper operation of collections that are derived from other objects. Specifically, it maintains proper synchronization with other threads that might be simultaneously modifying the object.

Enumerating through a collection is intrinsically not a thread-safe procedure. Even when a collection is synchronized, other threads could still modify the collection, which causes the enumerator to throw an exception. 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. For more information, see ICollection.IsSynchronized.

範例

The following code example shows how to lock an ArrayList collection using the SyncRoot during the enumeration.

using System;
using System.Collections;

ArrayList myCollection = new ArrayList();
lock( myCollection.SyncRoot ) 
foreach ( Object item in myCollection ) 
{
    // Insert your code here.
}

Imports System
Imports System.Collections

Dim myCollection As ArrayList =  New ArrayList() 

lock(myCollection.SyncRoot)
For Each item In myCollection
    ' Insert your code here.
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