Making the App Asynchronous

Previous: Introducing Fluent Assertions

As outlined briefly in Asynchronous programming, you should be writing asynchronous code when accessing a database. If operations may take a long time, you don't want to be locking up your threads.

When making a method async, you will need to change the return type to one of three things:
void Only used for event handlers
Task For when you want to wait for the method to finish, but don't care about a return value
Task<T> For when you want to wait for on the method call, and expect back an object of type T

In this app, we will only be using the last one.

The key to calling asynchronous methods is to use the keyword await. This will cause it to wait until the method has completed and return the result from within the Task<T>.

As part of best practices, we'll also be renaming our asynchronous methods to have the suffix Async now.

Note: There are also times were you may not need to have your method be async, but still want to take advantage of the consistency of making your methods return a Task<T> (this is good for your interfaces). In such a situation, you can employ Task.FromResult(x). What this means is that you can hand back a Task<T> that will return immediately when awaited.

Git Tag: making-the-app-asynchronous

Up Next: Delegating Data Responsibility

References
Asynchronous Programming Advice