在 mvc 中上传文件时，Visual Studio 调试会立即停止吗？

Question

So I'm trying to get into .NET Core MVC using Visual Studio 2019 Enterprise.

I tried to follow a fairly simple example from Microsofts own documentation . After setting up the code, I have the template project that they give you with MVC. So on the "About" page I have the following controller class AboutController.cs with the method found on Microsofts website:

[HttpPost("UploadFiles")]
public async Task<IActionResult> Post(List<IFormFile> files)
{
    long size = files.Sum(f => f.Length);
    string filePath = Path.GetTempFileName();

    if (files.Count > 0)
    {
        IFormFile file = files[0];
        if (file.Length > 0)
        {
            using (FileStream stream = new FileStream(filePath, FileMode.Create))
            {
                await file.CopyToAsync(stream);
            }
        }
    }

    return View();
}

The only "big" difference is that I return the view, not an "Ok" because I'm not really interested in that. I want to modify the view I'm looking at not go to a completely new view (maybe I'm misunderstanding how MVC works?).

Now my HTML looks like this:

<form method="post" enctype="multipart/form-data" asp-controller="About" asp-action="Post">
    <div class="form-group">
        <div class="col-md-10">
            <p>Upload one image using this form:</p>
            <input type="file" name="files">
        </div>
    </div>
    <div class="form-group">
        <div class="col-md-10">
            <input type="submit" value="Upload">
        </div>
    </div>
</form>

This produces the form, also as seen in their documentation linked earlier. When I click the "Browse" button to find a picture, it works fine and when I click "Open" so I can upload it, the Visual Studio debugger stops running immediately. No error anywhere that I can see.

Any idea what causes this behaviour?

Update 1

It appears that just calling return View(); exhibits the same behaviour and Nuget says it's AspNetCore.Mvc 2.1.1

Update 2

Turns out the debugger does not work in this particular instance with the browser called "Brave" which is a chromium browser that I use (which If forgot to mention)

Answer 1

This behavior in specific has been attributed to a browser problem and not Visual Studio in general. As per this article and this article, this behavior was generally observed when using browsers like Brave in this case and Yandex. Sometimes even Chrome shows this behavior but it is not consistent (at least that is what I have observed).

A possible solution would be changing your browser type to use ideal browsers like Chrome, Firefox or Edge.

Answer 2

I have the issue with Visual Studio 2017 Professional Edition (4.8)

And I am using Microsoft Edge Version 94.0.992.47.

So what I did is I restarted browser and Visual Studio and everything works fine afterwards. It's strange but restarting sometime works.