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What is the type of object that is returned from an asynchronous method?
You use the void return type in asynchronous event handlers, which require a void return type. For methods other than event handlers that don’t return a value, you should return a Task instead, because an async method that returns void can’t be awaited.
When should a method be async?
Asynchronous programming is a better fit for code that must respond to events – for example, any kind of graphical UI. An example of a situation where programmers use async but shouldn’t is any code that can focus entirely on data processing and can accept a “stop-the-world” block while waiting for data to download.
What is a key benefit of asynchronous processing?
Benefits of asynchronous processing are following. Higher governor and execution limits. Unlimited number of external callouts. Override organization-wide sharing defaults. Enabling turbo mode for transactional processing.
How to process asynchronous tasks as they complete?
The following example uses a query to create a collection of tasks. Each task downloads the contents of a specified website. In each iteration of a while loop, an awaited call to WhenAny returns the task in the collection of tasks that finishes its download first. That task is removed from the collection and processed.
How to throttle asynchronous methods in C #?
Select projects the collection of URIs to an IEnumerable . Task.WhenAll takes this IEnumerable and returns a single Task that completes when all of the Task s in the collection have completed. We’re now only awaiting this single Task. This will now begin to download all of the URIs at nearly the same time and process them concurrently.
How to use non-blocking asynchronous methods in C #?
Keeping all the tasks in a collection and calling await Task.WhenAll (tasks) at the end ensures the last tasks have completed. This approach is non-blocking and asynchronous, and will keep us at our desired degreeOfParallelism for the entire duration of the call.
How to process multiple tasks at the same time?
By using Task.WhenAny, you can start multiple tasks at the same time and process them one by one as they’re completed rather than process them in the order in which they’re started. The following example uses a query to create a collection of tasks. Each task downloads the contents of a specified website.