React-native-windows: Unable to build SimpleHttpModule in C# Example in RNW documentation

[getuliovdmnaweb]

Environment

Run the following in your terminal and copy the results here.

1. npx react-native --version: 4.13.0
2. npx react-native info:
   

Steps To Reproduce

1. Create a NativeModuleSample following this tutorial https://microsoft.github.io/react-native-windows/docs/native-modules-setup
2. Implement asyncronous windows following this example https://microsoft.github.io/react-native-windows/docs/native-modules-async#simplehttpmodule-in-c
3. Both the Example discribed there and the Implementation discribed here (https://github.com/microsoft/react-native-windows-samples/blob/master/samples/NativeModuleSample/csharp/windows/NativeModuleSample/AsyncMethodExamples.cs) should be tested.
   

   Expected Results

We should be able to build the Native Module Library

Snack, code example, screenshot, or link to a repository:

Example using the Documentation :

Example using Githubs Repository

[NickGerleman]

@getuliovdmnaweb does the example work if you change Task<string> to IAsyncOperation<string>? This seems like a potential docs issue.

FYI @dannyvv

[caiovictor]

Hi guys @NickGerleman @dannyvv @chrisglein @jonthysell, I have the same error as @getuliovdmnaweb , but when I create a constant using ReactConstantProvider:

This method I copied from that link:
https://github.com/microsoft/react-native-windows/blob/abee26d14b3ffed5210a97283a1353f38b0b1989/vnext/Microsoft.ReactNative.Managed.UnitTests/NativeModuleTest.cs#L498

Isn't this related to the public methods of a Windows Runtime project not being able to expose types that do not inherit from IAsyncInfo?

[jonthysell]

The NativeModuleSample builds just fine but does not match what's in the docs.

[jonthysell]

The documentation has been updated to reflect the working sample. Please re-open if the new code doesn't work.

[getuliovdmnaweb]

This is the Example:

This is the Error:

[getuliovdmnaweb]

@jonthysell I followed the updated documentation and the same problem still occurs.

[jonthysell]

@getuliovdmnaweb Can you post a link to your project source? It think this has less to do with the code and more to do with the structure of the solution/project files.

[getuliovdmnaweb]

@jonthysell Hello, here is the link to a github repository with the example
https://github.com/getuliovdmnaweb/NativeModuleSample

[jonthysell]

@jonthysell Hello, here is the link to a github repository with the example
https://github.com/getuliovdmnaweb/NativeModuleSample

As per the docs and samples, please remove public sealed from your module class, so that it defaults to an internal class.

-    public sealed class NativeModuleSample
+    class NativeModuleSample

Making a public WinRT class exports that class externally (to be consumed directly by any WinRT app/lib) however this requires that all public members and methods only use publicly available WinRT types. The types in Microsoft.ReactNative.Managed (such as JSValue and ReactPromise<>) are not publicly available WinRT types, as Microsoft.ReactNative.Managed is a just a Class Library, not a WinRT Library.

The expectation is that your project only exposes the ReactPackageProvider - everything else should be internal types.