Bad await FromResult examples

[olivier-net]

Type of issue

Missing information

Description

There are 2 places in the page where it does return await Task.FromResult(new User() { id = userId }); await and Task.FromResult are the opposite, the should not be use together.

Also, there are no example on what to do if the method is synchronous but must return a Task, ex: when implementing an interface.

Page URL

https://learn.microsoft.com/en-us/dotnet/csharp/asynchronous-programming/async-scenarios

Content source URL

https://github.com/dotnet/docs/blob/main/docs/csharp/asynchronous-programming/async-scenarios.md

Document Version Independent Id

77bdee53-c2a0-e16f-c93a-3ca0afae0b93

Article author

@BillWagner

Metadata

• ID: d885f1eb-2b37-693b-c91f-74b748c9424a
• Service: dotnet-csharp
• Sub-service: async-task-programming

Related Issues

[BillWagner]

hi @olivier-net

This is an area that needs more work.

Short answers to your comments:

• The Task.FromResult is the correct way to create a task when you need to return a completed task, possibly with a result, in a synchronous method. In general, Task.FromResult(true) is the typical pattern for a Task that doesn't include a result.
• Yes, the only reason to use await Task.FromResult(...) is to force the compiler to generate the async state machine (because of the await). That shouldn't be used here.