Array.IsSynchronized Property

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

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

Namespace: System
Assembly: mscorlib (in mscorlib.dll)


Public ReadOnly Property IsSynchronized As Boolean
public bool IsSynchronized { get; }

Property Value

Type: System..::.Boolean
This property is always false for all arrays.




Array implements the IsSynchronized property because it is required by the System.Collections..::.ICollection interface.

.NET Framework classes based on Array provide their own synchronized version of the collection using the SyncRoot property.

Classes that use arrays can also implement their own synchronization 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 collection. Note that some implementations of SyncRoot might return the Array itself.

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.

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


The following code example shows how to lock an array during the entire enumeration by using the SyncRoot property.

Dim myArray As Array = New Integer() {1, 2, 4}
SyncLock (myArray.SyncRoot)
   For Each item As Object In myArray
      outputBlock.Text += item + vbCrLf
End SyncLock
Array myArray = new int[] { 1, 2, 4 };
lock (myArray.SyncRoot)
   foreach (Object item in myArray)
      outputBlock.Text += item + "\n";

Version Information

Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0


Windows Phone

See Also


Array Class

System Namespace