File Upload in API. in Dotnet core WPF Windows App

问题:

Upload File in API. (with Body From-Data) in the Dotnet core, WPF Windows Application (Also Can in Web Controller). and Successfully upload Files.

Model Class

public class TestDocumentModel
{
    public int Id { get; set; }
    public string Name { get; set; }
    public IFormFile formFiles { get; set; }
}

API Controller

    public async Task<IActionResult> UploadModelFiles([FromForm]TestDocumentModel models)
    {

        var filePath = Path.Combine(@"Custome File Save Path");

        if (models.formFiles != null)
        {
            long sizeOfFile = models.formFiles.Length;
            if (filePath.Length > 0)
            {
                if (!Directory.Exists(filePath))
                {
                    Directory.CreateDirectory(filePath);

                    if (Directory.Exists(filePath))
                    {
                      using (var fileStream = new FileStream(Path.Combine(filePath, models.formFiles.FileName), FileMode.Create))
                      {
                        await models.formFiles.CopyToAsync(fileStream);
                      }
                   }
                }
            }
            return Ok(new { sizeOfFile, filePath });
        }
        else
        {
            long fileSize = 0;
            filePath = "File note Found";
            return Ok(new { fileSize, filePath });
        }
    }

Web Controller or WPF Windows Application Class

          obj = new TestModelClass();

        if (dlg != null)
        {
            using (var httpClient = new HttpClient())
            {
                string fileName = dlg.SafeFileName;
                using (var content = new MultipartFormDataContent())
                {
                    obj.Id = int.Parse(tb_id.Text);
                    obj.Name = tb_name.Text;
                    FileStream fileStream = File.OpenRead(dlg.FileName);
                    HttpContent fileStreamContent = new StreamContent(fileStream);

                    content.Add(new StringContent(Convert.ToString(obj.Id)), "Id");
                    content.Add(new StringContent(Convert.ToString(obj.Name)), "Name");
                    fileStreamContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data") { Name = "formFiles", FileName = fileName };
                    fileStreamContent.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");

                    content.Add(fileStreamContent);

                    using (var response = await httpClient.PostAsync("https://localhost:44359/weatherforecast/UploadModelFiles", content))
                    {
                        string apiResponse = await response.Content.ReadAsStringAsync();
                    }
                }
            }
        }

File post in API Form Postman (And Successfully upload)

File post in API Form Web/WPF Windows App (But File is Corrupted or damaged.)