DTSReadOnlyCollectionBase.SyncRoot Property

Article
07/16/2015

Applies To: SQL Server 2016 Preview

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

Namespace: Microsoft.SqlServer.Dts.Runtime
Assembly: Microsoft.SqlServer.ManagedDTS (in Microsoft.SqlServer.ManagedDTS.dll)

Syntax

public object SyncRoot { get; }

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

abstract SyncRoot : Object with get
override SyncRoot : Object with get

Public ReadOnly Property SyncRoot As Object

Property Value

Type: System.Object

An object that can be used to synchronize access to the DTSReadOnlyCollectionBase.

Implements

ICollection.SyncRoot

Remarks

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.

Examples

Legacy Code Example

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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