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CancellationToken.Register Method (Action<Object>, Object)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Registers a delegate that will be called when this CancellationToken is canceled.

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

Syntax

'Declaration
Public Function Register ( _
    callback As Action(Of Object), _
    state As Object _
) As CancellationTokenRegistration

public CancellationTokenRegistration Register(
    Action<Object> callback,
    Object state
)

Parameters

  • state
    Type: System.Object
    The state to pass to the callback when the delegate is invoked. This may be null.

Return Value

Type: System.Threading.CancellationTokenRegistration
The CancellationTokenRegistration instance that can be used to deregister the callback.

Exceptions

Exception Condition
ObjectDisposedException

The associated CancellationTokenSource has been disposed.
ArgumentNullException

callback is null.

Remarks

If this token is already in the canceled state, the delegate will be run immediately and synchronously. Any exception the delegate generates will be propogated out of this method call.

The current ExecutionContext, if one exists, will be captured along with the delegate and will be used when executing it.

Version Information

Silverlight

Supported in: 5

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.