DispatcherQueue.TryEnqueue Method
Definition
Important
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Overloads
| TryEnqueue(DispatcherQueueHandler) |
Adds a task to the DispatcherQueue that will be executed on the thread associated with the DispatcherQueue. |
| TryEnqueue(DispatcherQueuePriority, DispatcherQueueHandler) |
Adds a task to the DispatcherQueue that will be executed on the thread associated with the DispatcherQueue with the specified priority. |
TryEnqueue(DispatcherQueueHandler)
Adds a task to the DispatcherQueue that will be executed on the thread associated with the DispatcherQueue.
public:
virtual bool TryEnqueue(DispatcherQueueHandler ^ callback) = TryEnqueue;[Windows.Foundation.Metadata.Overload("TryEnqueue")]
public bool TryEnqueue(DispatcherQueueHandler callback);function tryEnqueue(callback)Public Function TryEnqueue (callback As DispatcherQueueHandler) As BooleanParameters
- callback
- DispatcherQueueHandler
A delegate to the task to execute.
Returns
bool
True if the task was added to the queue. Otherwise, false.
- Attributes
Examples
The following example shows how to create a new thread and initialize a DispatcherQueueController and run a DispatcherQueue event loop on it.
// Create a new thread and initialize a DispatcherQueueController
// and run a DispatcherQueue event loop on it.
_queueController =
DispatcherQueueController.CreateOnDedicatedThread();
_queue = _queueController.DispatcherQueue;
// This is the first TryEnqueue() after creating the DispatcherQueue. The
// first TryEnqueue task is guaranteed to be invoked first on the new
// thread.
bool isQueued = _queue.TryEnqueue(
() =>
{
// task to perform on another thread.
});
Remarks
The queue will invoke callback serially.
Once ShutdownQueueAsync() has been called, the queue will not queue new tasks and this method will return false.
Applies to
TryEnqueue(DispatcherQueuePriority, DispatcherQueueHandler)
Adds a task to the DispatcherQueue that will be executed on the thread associated with the DispatcherQueue with the specified priority.
public:
virtual bool TryEnqueue(DispatcherQueuePriority priority, DispatcherQueueHandler ^ callback) = TryEnqueue;[Windows.Foundation.Metadata.Overload("TryEnqueueWithPriority")]
public bool TryEnqueue(DispatcherQueuePriority priority, DispatcherQueueHandler callback);function tryEnqueue(priority, callback)Public Function TryEnqueue (priority As DispatcherQueuePriority, callback As DispatcherQueueHandler) As BooleanParameters
- priority
- DispatcherQueuePriority
The priority of the task (such as Low, Normal, or High).
- callback
- DispatcherQueueHandler
A delegate to the task to execute.
Returns
bool
True if the task was added to the queue. Otherwise, false.
- Attributes
Examples
The following example shows how to create a new thread and initialize a DispatcherQueueController and run a DispatcherQueue event loop on it.
// Create a new thread and initialize a DispatcherQueueController
// and run a DispatcherQueue event loop on it.
_queueController =
DispatcherQueueController.CreateOnDedicatedThread();
_queue = _queueController.DispatcherQueue;
// This is the first TryEnqueue() after creating the DispatcherQueue. The
// first TryEnqueue task is guaranteed to be invoked first on the new
// thread, regardless of what priority it was enqueued at.
bool isQueued = _queue.TryEnqueue(Windows.System.DispatcherQueuePriority.High,
() =>
{
// task to perform on another thread.
});
Remarks
The queue will invoke callback serially and in priority order.
Once ShutdownQueueAsync() has been called, the queue will not queue new tasks and this method will return false.