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CancellationTokenSource Class

Signals to a CancellationToken that it should be canceled.


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

[HostProtectionAttribute(SecurityAction.LinkDemand, Synchronization = true, 
	ExternalThreading = true)]
public sealed class CancellationTokenSource : IDisposable

The CancellationTokenSource type exposes the following members.

Public methodCancellationTokenSourceInitializes the CancellationTokenSource.

Public propertyIsCancellationRequestedGets whether cancellation has been requested for this CancellationTokenSource.
Public propertyTokenGets the CancellationToken associated with this CancellationTokenSource.

Public methodCancel()Communicates a request for cancellation.
Public methodCancel(Boolean)Communicates a request for cancellation.
Public methodStatic memberCreateLinkedTokenSource(CancellationToken[])Creates a CancellationTokenSource that will be in the canceled state when any of the source tokens are in the canceled state.
Public methodStatic memberCreateLinkedTokenSource(CancellationToken, CancellationToken)Creates a CancellationTokenSource that will be in the canceled state when any of the source tokens are in the canceled state.
Public methodDisposeReleases all resources used by the current instance of the CancellationTokenSource class.
Public methodEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

For more information and code examples see Cancellation.


The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: Synchronization | ExternalThreading. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

All public and protected members of CancellationTokenSource are thread-safe and may be used concurrently from multiple threads, with the exception of Dispose, which must only be used when all other operations on the CancellationTokenSource have completed.