It’s been a while since our last part in the C# 8 series, but here it is! We will continue our journey through the new language features, and dive into async streams.
In this series, we are looking at:
- Indices, Ranges, and Null-coalescing Assignments
- Switch Expressions and Pattern-Based Usings
- Recursive Pattern Matching
- Async Streams
- Nullable Reference Types
Asynchronous programming is a form of programming that prevents blocking of our application by allowing time-consuming work – like downloading data from a network – to be decoupled from the main thread. For our implementation, in principal, it requires to hand over a callback to the asynchronous method, that in turn will invoke the callback when it has finished its work.
With C# 5, the async and await keywords have been introduced. These fundamentally improved how we can write and consume asynchronous methods. Basically, the structure of our code can remain almost the same compared to a synchronous implementation, but the compiler takes over a whole lot of work to restructure our code into mentioned callbacks to make it stateful and non-blocking. This, though, only worked for void and single-result methods using Task and Task<T> as return type.
Methods producing streams of data – a.k.a. IEnumerable<T> – were left out, and required custom code to be written. However, such requirements are quite popular, thinking of working with cloud applications, collecting data from IoT sensors, or receiving data from databases. Hello, C# 8 and IAsyncEnumerable!
