IFormFileCollection minimal api behave different from mvc controller

[kzhui125]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

I can get files with minimal api.
I can't get files with mvc controller.

Expected Behavior

No response

Steps To Reproduce

MapPost:

app.MapPost("/MinimalApi/Upload", async (IFormFileCollection files) =>
{
    await Task.CompletedTask;
    return Results.Ok(files.Count);
});

MapController:

[ApiController]
[Route("api/[controller]")]
public class TestController : ControllerBase
{
    // /Test/Upload
    [HttpPost("Upload")]
    public async Task<IActionResult> Upload([FromForm] IFormFileCollection files)
    {
        await Task.CompletedTask;
        return Ok(files.Count);
    }
}

Call await UploadAsync(urlMinimalApi) and await UploadAsync(urlMvcController)

the responseContent of MinimalApi is 2 (expected).
the responseContent of MvcController is 0 (unexpected).

private async Task UploadAsync(string url)
{
    using HttpClient httpClient = new();

    var content = new MultipartFormDataContent();

    using var stream1 = new MemoryStream("Content1"u8.ToArray());
    var fileContent1 = new StreamContent(stream1);
    fileContent1.Headers.ContentType = MediaTypeHeaderValue.Parse("application/octet-stream");
    content.Add(fileContent1, "File1", "File1.txt");

    using var stream2 = new MemoryStream("Content2"u8.ToArray());
    var fileContent2 = new StreamContent(stream2);
    fileContent2.Headers.ContentType = MediaTypeHeaderValue.Parse("application/octet-stream");
    content.Add(fileContent2, "File2", "File2.txt");

    var response = await httpClient.PostAsync(url, content);
    response.EnsureSuccessStatusCode();

    string responseContent = await response.Content.ReadAsStringAsync();

    Console.WriteLine(responseContent);
}

Exceptions (if any)

No response

.NET Version

7.0.304

Anything else?

What's wrong with my code? Or there is a bug in http client?

Thanks for your help.

[kzhui125]

Update:

if the HTTP content item name is "files", then the minimal api works the same as mvc controller.

content.Add(fileContent1, "files", "File1.txt");
content.Add(fileContent2, "files", "File2.txt");

It seems that because of minimal api lacks form binding support (#39430), cause the inconsistent behavior with mvc controller.