Async in C# 5.0 by Davies, Alex -- Read -- Imperial Library of Trantor

Index

Async in C# 5.0 Preface

Intended Audience How to Read This Book Conventions Used in This Book Using Code Examples Safari® Books Online How to Contact Us Acknowledgments

1. Introduction

Asynchronous Programming What’s So Great About Asynchronous Code? What Is Async? What Async Does Async Doesn’t Solve Everything

2. Why Programs Need to Be Asynchronous

Desktop User Interface Applications

An Analogy: The Cafe

Web Application Server Code

Another Analogy: The Restaurant Kitchen

Silverlight, Windows Phone, and Windows 8 Parallel Code An Example

3. Writing Asynchronous Code Manually

Some Asynchronous Patterns Used in .NET The Simplest Asynchronous Pattern An Introduction to Task The Problem with Manual Asynchrony Converting the Example to Use Manual Asynchronous Code

4. Writing Async Methods

Converting the Favicon Example to Async Task and await Async Method Return Types Async, Method Signatures, and Interfaces The return Statement in Async Methods Async Methods Are Contagious Async Anonymous Delegates and Lambdas

5. What await Actually Does

Hibernating and Resuming a Method The State of the Method Context Where await Can’t Be Used

catch and finally Blocks lock Blocks LINQ Query Expressions Unsafe Code

Exception Capture Async Methods Are Synchronous Until Needed

6. The Task-Based Asynchronous Pattern

What the TAP Specifies Using Task for Compute-Intensive Operations Creating a Puppet Task Interacting with Old Asynchronous Patterns Cold and Hot Tasks Up-Front Work

7. Utilities for Async Code

Delaying for a Period of Time Waiting for a Collection of Tasks Waiting for Any One Task from a Collection Creating Your Own Combinators Cancelling Asynchronous Operations Returning Progress During an Asynchronous Operation

8. Which Thread Runs My Code?

Before the First await During the Asynchronous Operation SynchronizationContext in Detail await and SynchronizationContext The Lifecycle of an Async Operation Choosing Not to Use SynchronizationContext Interacting with Synchronous Code

9. Exceptions in Async Code

Exceptions in Async Task-Returning Methods Unobserved Exceptions Exceptions in Async void Methods Fire and Forget AggregateException and WhenAll Throwing Exceptions Synchronously finally in Async Methods

10. Parallelism Using Async

await and locks Actors Using Actors in C# Task Parallel Library Dataflow

11. Unit Testing Async Code

The Problem with Unit Testing in Async Writing Working Async Tests Manually Using Unit Test Framework Support

12. Async in ASP.NET Applications

Advantages of Asynchronous Web Server Code Using Async in ASP.NET MVC 4 Using Async in Older Versions of ASP.NET MVC Using Async in ASP.NET Web Forms

13. Async in WinRT Applications

What Is WinRT? IAsyncAction and IAsyncOperation<T> Cancellation Progress Providing Asynchronous Methods in a WinRT Component

14. The Async Compiler Transform—in Depth

The stub Method The State Machine Struct The MoveNext Method

Your Code Transforming Returns to Completions Get to the Right Place in the Method Pausing the Method for the await Resuming after the Await Completing Synchronously Catching Exceptions More Complicated Code

Writing Custom Awaitable Types Interacting with the Debugger

15. The Performance of Async Code

Measuring Async Overhead Async Versus Blocking for a Long-Running Operation Optimizing Async Code for a Long-Running Operation Async Versus Manual Asynchronous Code Async Versus Blocking Without a Long-Running Operation Optimizing Async Code Without a Long-Running Operation Async Performance Summary

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