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SyncRoot Property
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StringDictionary::SyncRoot Property

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

Namespace:  System.Collections.Specialized
Assembly:  System (in System.dll)

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

Property Value

Type: System::Object
An Object that can be used to synchronize access to the StringDictionary.

Derived classes can provide their own synchronized version of the StringDictionary using the SyncRoot property. The synchronizing code must perform operations on the SyncRoot of the StringDictionary, not directly on the StringDictionary. 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 StringDictionary object.

Enumerating through a collection is intrinsically not a thread-safe procedure. Even when a collection is synchronized, other threads can 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.

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

StringDictionary^ myCollection = gcnew StringDictionary();
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);
    }
}

Retrieving the value of this property is an O(1) operation.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0
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