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System.Threading Namespace

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The System.Threading namespace provides classes and interfaces that enable multithreaded programming. In addition to classes for synchronizing thread activities and access to data (Monitor, Interlocked, AutoResetEvent, and so on), this namespace includes a ThreadPool class that enables you to use a pool of system-supplied threads, and a Timer class that executes callback methods on thread pool threads. In addition to the features provided in the System.Threading namespace, the BackgroundWorker class provides a simple, event-based way to synchronize access to the main application thread.

Classes

  Class Description
Public class AutoResetEvent Notifies a waiting thread that an event has occurred. This class cannot be inherited.
Public class CancellationTokenSource Signals to a CancellationToken that it should be canceled.
Public class EventWaitHandle Represents a thread synchronization event.
Public class Interlocked Provides atomic operations for variables that are shared by multiple threads.
Public class ManualResetEvent Notifies one or more waiting threads that an event has occurred. This class cannot be inherited.
Public class Monitor Provides a mechanism that synchronizes access to objects.
Public class Mutex A synchronization primitive that can also be used for interprocess synchronization.
Public class Overlapped Provides a managed representation of a Win32 OVERLAPPED structure, including methods to transfer information from an Overlapped instance to a NativeOverlapped structure.
Public class RegisteredWaitHandle Represents a handle that has been registered when calling RegisterWaitForSingleObject. This class cannot be inherited.
Public class SynchronizationContext Provides the basic functionality for propagating a synchronization context in various synchronization models.
Public class SynchronizationLockException The exception that is thrown when a method requires the caller to own the lock on a given Monitor, and the method is invoked by a caller that does not own that lock.
Public class Thread Creates and controls a thread, and gets its status.
Public class ThreadAbortException The exception that is thrown when a call is made to the Abort method. This class cannot be inherited.
Public class ThreadPool Provides a pool of threads that can be used to post work items, process asynchronous I/O, wait on behalf of other threads, and process timers.
Public class ThreadStartException The exception that is thrown when a failure occurs in a managed thread after the underlying operating system thread has been started, but before the thread is ready to execute user code.
Public class ThreadStateException The exception that is thrown when a Thread is in an invalid ThreadState for the method call.
Public class Timeout Contains a constant that is used to specify an infinite amount of time. This class cannot be inherited.
Public class Timer Provides a mechanism for executing a method at specified intervals. This class cannot be inherited.
Public class WaitHandle Encapsulates operating system–specific objects that wait for exclusive access to shared resources.

Structures

  Structure Description
Public structure CancellationToken Propagates notification that operations should be canceled.
Public structure CancellationTokenRegistration Represents a callback delegate that has been registered with a CancellationToken.
Public structure NativeOverlapped Provides an explicit layout that is visible from unmanaged code and that will have the same layout as the Win32 OVERLAPPED structure with additional reserved fields at the end.

Delegates

  Delegate Description
Public delegate IOCompletionCallback Receives the error code, number of bytes, and overlapped value type when an I/O operation completes on the thread pool.
Public delegate ParameterizedThreadStart Represents the method that executes on a Thread.
Public delegate SendOrPostCallback Represents a method to be called when a message is to be dispatched to a synchronization context.
Public delegate ThreadStart Represents the method that executes on a Thread.
Public delegate TimerCallback Represents the method that handles calls from a Timer.
Public delegate WaitCallback Represents a callback method to be executed by a thread pool thread.
Public delegate WaitOrTimerCallback Represents a method to be called when a WaitHandle is signaled or times out.

Enumerations

  Enumeration Description
Public enumeration LazyThreadSafetyMode Specifies how a System.Lazy<T> instance synchronizes access among multiple threads.
Public enumeration ThreadState Specifies the execution states of a Thread.