Concurrency::task_continuation_context Class Reference

The task_continuation_context class allows you to specify where you would like a continuation to be executed. It is only useful to use this class from a Windows Store app. For non-Windows Store apps, the task continuation's execution context is determined by the runtime, and not configurable. More...

#include <ppltasks.h>

Inheritance diagram for Concurrency::task_continuation_context:

Public Member Functions
bool	_ForceInline () const
Public Member Functions inherited from Concurrency::details::_ContextCallback
	~_ContextCallback ()
	_ContextCallback (bool _DeferCapture=false)
void	_Resolve (bool _CaptureCurrent)
	_ContextCallback (const _ContextCallback &_Src)
	_ContextCallback (_ContextCallback &&_Src)
_ContextCallback &	operator= (const _ContextCallback &_Src)
_ContextCallback &	operator= (_ContextCallback &&_Src)
bool	_HasCapturedContext () const
bool	operator== (const _ContextCallback &_Rhs) const
bool	operator!= (const _ContextCallback &_Rhs) const
_CRTIMP2 void __thiscall	_CallInContext (_CallbackFunction _Func, bool _IgnoreDisconnect) const
void	_CallInContext (_CallbackFunction _Func) const

Static Public Member Functions
static task_continuation_context	use_default ()
	Creates the default task continuation context. More...
static task_continuation_context	get_current_winrt_context ()
	Returns a task continuation context object that represents the current winrt thread context. More...
static task_continuation_context	use_synchronous_execution ()
	Returns a task continuation context object that represents the synchronous execution context. More...
Static Public Member Functions inherited from Concurrency::details::_ContextCallback
static _ContextCallback	_CaptureCurrent ()

Private Member Functions
_CRTIMP2 __thiscall	task_continuation_context ()

Private Attributes
bool	_M_RunInline

Detailed Description

The task_continuation_context class allows you to specify where you would like a continuation to be executed. It is only useful to use this class from a Windows Store app. For non-Windows Store apps, the task continuation's execution context is determined by the runtime, and not configurable.

See also

task Class

Constructor & Destructor Documentation

_CRTIMP2 __thiscall Concurrency::task_continuation_context::task_continuation_context ( )

private

Member Function Documentation

bool Concurrency::task_continuation_context::_ForceInline ( ) const

inline

    {
        return _M_RunInline;
    }

static task_continuation_context Concurrency::task_continuation_context::get_current_winrt_context ( )

inlinestatic

Returns a task continuation context object that represents the current winrt thread context.

Returns

The current winrt thread context.

This method captures the current caller's Windows Runtime thread context. It is very similar to what task_continuation_context::use_current() is doing except it is also available without C++/Cx extension support. Please approach this method with caution as it is designed for advanced users writing C++/Cx agnostic library code. task_continuation_context::use_current() will give you more protection from mistakes.

This method is only available to Windows Store apps.

    {
        task_continuation_context _Current;
        _Current._Resolve(true);
        return _Current;
    }

static task_continuation_context Concurrency::task_continuation_context::use_default ( )

inlinestatic

Creates the default task continuation context.

Returns

The default continuation context.

The default context is used if you don't specify a continuation context when you call the then method. In Windows applications for Windows 7 and below, as well as desktop applications on Windows 8 and higher, the runtime determines where task continuations will execute. However, in a Windows Store app, the default continuation context for a continuation on an apartment aware task is the apartment where then is invoked.

An apartment aware task is a task that unwraps a Windows Runtime IAsyncInfo interface, or a task that is descended from such a task. Therefore, if you schedule a continuation on an apartment aware task in a Windows Runtime STA, the continuation will execute in that STA.

A continuation on a non-apartment aware task will execute in a context the Runtime chooses.

    {
        return task_continuation_context();
    }

static task_continuation_context Concurrency::task_continuation_context::use_synchronous_execution ( )

inlinestatic

Returns a task continuation context object that represents the synchronous execution context.

Returns

The synchronous execution context.

This method will force the continuation task synchronously running on the context causing its antecedent task's completion; if the antecedent task has completed when the continuation is attached, the continuation will synchronously run on the context that attaches the continuation.

    {
        task_continuation_context _Current;
        _Current._Resolve(false);
        _Current._M_RunInline = true;
        return _Current;
    }

Member Data Documentation

bool Concurrency::task_continuation_context::_M_RunInline

private

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The documentation for this class was generated from the following file:

• VS2017/inc/ppltasks.h