CancellationToken.IsCancellationRequested Property


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Gets whether cancellation has been requested for this token.

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

member IsCancellationRequested : bool with get

Property Value

Type: System.Boolean

true if cancellation has been requested for this token; otherwise, false.

This property indicates whether cancellation has been requested for this token, either through the token initially being constructed in a canceled state, or through calling Cancel on the token's associated CancellationTokenSource.

If this property is true, it only guarantees that cancellation has been requested. It does not guarantee that every registered handler has finished executing, nor that cancellation requests have finished propagating to all registered handlers. Additional synchronization may be required, particularly in situations where related objects are being canceled concurrently.

The following is a simple example that executes a server process until the IsCancellationRequested property returns true.

No code example is currently available or this language may not be supported.

The example instantiates a CancellationTokenSource object, which controls access to the cancellation token. It then defines two thread procedures. The first is defined as a lambda expression that pools the keyboard and, when the "C" key is pressed, calls CancellationTokenSource.Cancel to set the cancellation token to the cancelled state. The second is a parameterized method, ServerClass.StaticMethod, that executes a loop until the IsCancellationRequested property is true.

The main thread then starts the two threads and blocks until the thread that executes the ServerClass.StaticMethod method terminates.

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Available since 5.0
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
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