Queue.IsSynchronized Property

Definition

Namespace:

System.Collections

Assemblies:

netstandard.dll, System.Collections.NonGeneric.dll

Source:

Queue.cs

Gets a value indicating whether access to the Queue is synchronized (thread safe).

C#

public virtual bool IsSynchronized { get; }

Property Value

Boolean

true if access to the Queue is synchronized (thread safe); otherwise, false. The default is false.

Implements

IsSynchronized

Examples

The following code example shows how to lock the collection using the SyncRoot during the entire enumeration. Retrieving the value of this property is an O(1) operation.

C#

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

The following example shows how to synchronize a Queue, determine if a Queue is synchronized, and use a synchronized Queue.

C#

using System;
using System.Collections;

public class SamplesQueue
{
    public static void Main()
    {
        // Creates and initializes a new Queue.
        Queue myQ = new Queue();
        myQ.Enqueue("The");
        myQ.Enqueue("quick");
        myQ.Enqueue("brown");
        myQ.Enqueue("fox");

        // Creates a synchronized wrapper around the Queue.
        Queue mySyncdQ = Queue.Synchronized(myQ);

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

myQ is not synchronized.
mySyncdQ is synchronized.
*/

Remarks

To guarantee the thread safety of the Queue, all operations must be done through the wrapper returned by the Synchronized method.

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.

Applies to

See also

• SyncRoot
• Synchronized(Queue)