Most new .NET Framework APIs that have a significant latency will have asynchronous (async) methods. For example, the .NET HTTP client (superseding the web client), SMTP client, and Entity Framework (EF) all have async versions of common methods. In fact, the async version is usually the native implementation and the non-async method is simply a blocking wrapper to it. These methods are very beneficial and you should use them. However, they may not have the effect that you imagine when applied to web application programming.
Note
We will cover async operations and asynchronous architecture later in this book. We'll also go into Message Queuing (MQ) and worker services. This chapter is just a quick introduction, and we will simply show you some tools to go after the low-hanging fruit on web applications.
An async API returns control to the calling method before it completes. This can also be awaited so that, on completion, the execution resumes from where the asynchronous...