[BUG] Content-Type of Header causes a 415 error in WebAPI

[bestpika]

Describe the bug

I have a WebAPI function as follows.

• LoginController.cs

[HttpPost]
public Login Post([FromBody] string token)
{
  ...
}

• BaseAPI.cs

[Post("/api/login")]
Task<Login> Login([Body] string token);

I found that "HTTP 415 Unsupported Media Type" keeps appearing when sending data. Then when I checked the sent data, I found that the "Content-Type" is "text/plain; charset=UTF-8". However, the WebAPI in dot NET 6 only accepts "application/json" data, so I tried to modify the header, but I found that no matter how I modify it, there is an extra paragraph "text/plain; charset=UTF-8" in front of it.

Steps To Reproduce

Expected behavior

Screenshots

Environment

• Blazor .NET 6 PWA
• Edge 99.0.1150.11 beta x64

Additional context

[rorpage]

I am experiencing this as well when trying to POST SOAP XML to an endpoint.

Resulting header: Content-Type: text/plain; charset=utf-8, application/soap+xml; charset=utf-8

Interface:

    [Headers("Content-type: application/soap+xml; charset=utf-8")]
    public interface ISOAPAPI
    {
        [Post("/service.asmx")]
        Task PostDocument([Body] string xmlDocument);
    }

This exists in 6.3.2 and 6.2.16. I will keep trying other versions.

[rorpage]

@bestpika I got mine to work by changing the Headers to be:

[Headers("Content-Type: application/soap+xml; charset=utf-8")]

Specifically, Content-Type with a capital C and T.

[james-s-tayler]

This would be the kind of thing it would be handy to have a Roslyn Analyzer for...