o
o
Task Usage:

Task<int> longTask = LongRunningCalculation()
 Task starts immediately.
 Runs to first await in LongRunningCalculation() on current thread.
 Returned Task<int> can be passed around to be awaited in the future.

await longTask
 Does not block current thread.
 Unwraps Task<int> into int.
 Throws first exception that is triggered.

longTask.Wait()
 Blocks current thread until longTask has completed.
 Throws AggregateException which needs to be unwrapped to find triggered exception.

longTask.Wait(Timespan.FromSeconds(5))
 Blocks current thread until longTask has completed or the timeout has occurred.
 Throws AggregateException which needs to be unwrapped to find triggered exception.
 Returns true when longTask ran to completion, and false when longTask timed out.
 longTask may still be running even after the timeout.

longTask.Result
 Blocks current thread until longTask has completed.
 Unwraps Task<int> into int.
 Throws AggregateException which needs to be unwrapped to find triggered exception.

longTask.GetAwaiter().GetResult()
 Blocks current thread until longTask has completed.
 Unwraps Task<int> into int.
 Throws first exception that is triggered.
Batch Task Usage:

Task<int>[] longTasks =
{ LongRunningCalculation(), LongRunningCalculation(), LongRunningCalculation() }
 All tasks start immediately.
 All tasks run to first await in each LongRunningCalculation() on current thread.

Task.WhenAll(longTasks)
 Batches up all of longTasks into a single awaitable task.
 Runs all of longTasks in parallel when scheduling permits.
 Returned Task<int[]> can be passed around to be awaited in the future.

await Task.WhenAll(longTasks)
 Does not block current thread.
 Unwraps Task<int[]> into int[].
 Finishes running all tasks before any exception is thrown.
 Throws first exception that is triggered.

Task.WaitAll(longTasks)
 Blocks current thread until all longTasks have completed.
 Finishes running all tasks before any exception is thrown.
 Throws AggregateException which needs to be unwrapped to find triggered exception.

Task.WaitAll(longTasks, Timespan.FromSeconds(5))
 Blocks current thread until all longTasks have completed or the timeout has
occurred.
 Finishes running all tasks before exception is thrown.
 Throws AggregateException which needs to be unwrapped to find triggered exception.
 Returns true when longTasks all ran to completion, and false when longTasks timed
out.
 longTasks may still be running even after the timeout.
o
o
Configuring Task Await Options:

await longTask.ConfigureAwait(false)
 Configures the task to not need to return to the synchronization context it was
originally invoked with. The context is usually the thread it was invoked on.
 Lowers chance of deadlocks and should be preferred.

await longTask.ConfigureAwait(true)
 Configures the task to need to return to the synchronization context it was
originally invoked with. The context is usually the thread it was invoked on.
 This is the default for awaited tasks without calling .ConfigureAwait().
 Usually used when modifying UI elements that need to occur on the UI thread.
Function Definitions:

int Method()
 Method can internally contain Tasks.
 Method can internally .Wait() Tasks.
 Method cannot internally await Tasks.
 Method can return int.
 Method cannot be awaited on externally.
 Can externally catch exceptions thrown by Method.

Task<int> Method()
 Method can internally contain Tasks.
 Method can internally .Wait() Tasks.
 Method cannot internally await Tasks.
 Method can return Task<int>.
 Method can be awaited on externally.
 Can externally catch exceptions thrown by Method when awaited.

async Task<int> Method()
 Method can internally contain Tasks.
 Method can internally .Wait() Tasks.
 Method can internally await Tasks.
 Method can return int.
 Method can be awaited on externally.
 Can externally catch exceptions thrown by Method when awaited.

Task Method()
 Method can internally contain Tasks.
 Method can internally .Wait() Tasks.
 Method cannot internally await Tasks.
 Method can return Task.
 Method can be awaited on externally.
 Can externally catch exceptions thrown by Method when awaited.

async Task Method()
 Method can internally contain Tasks.
 Method can internally .Wait() Tasks.
 Method can internally await Tasks.
 Method cannot return anything.
 Method can be awaited on externally.
 Can externally catch exceptions thrown by Method when awaited.

async void Method()
 Method can internally contain Tasks.
 Method can internally .Wait() Tasks.
 Method can internally await Tasks.
 Method cannot return anything.
 Method cannot be awaited on externally.
 Cannot externally catch exceptions thrown by Method.
 Usually used as an async event delegate function definition, any other situation
should use async Task or async Task<T>.