Everything You (Don’t) Want to Know About Async and Await in C#

on YouTube ↗01h 11m

" summary

Deep dive into how C# rewrites async/await into a compiler-generated state machine: demos show Task.Delay(500/1000ms), printed thread IDs, and live polls (≈41–48 votes) that reveal a console app has no SynchronizationContext so continuations go to the thread pool (configureAwait has no effect there). Covers exception surfacing via GetResult, three task terminal states, cooperative cancellation patterns, async streams with cancellation, pitfalls of async void and ValueTask, and a working custom awaiter for Control.Dispatcher to marshal back to UI.

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" chapters (12)

1. 0:00Introduction and motivation
2. 2:20Async/await fundamentals
3. 5:05Control flow in async methods
4. 12:00Task combinators and parallelism
5. 14:40Under the hood: The state machine
6. 23:40Task states and exception handling
7. 27:20Cooperative cancellation
8. 31:50Advanced task patterns
9. 40:20Custom awaitables
10. 50:40Async streams and disposal
11. 56:30Reporting progress
12. 58:50Context and ConfigureAwait

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