Upload Image using Multipart Form

Question

I have a "choose" button to select an image from the device using FileOpenPicker and a "jawab" button to upload the image to the server using a multipart form

Code:

private Stream stream = new MemoryStream();
private async void chooseBtn_Click(object sender, RoutedEventArgs e)
{
    FileOpenPicker open = new FileOpenPicker();
    open.SuggestedStartLocation = PickerLocationId.PicturesLibrary;
    open.ViewMode = PickerViewMode.Thumbnail;
    open.FileTypeFilter.Clear();
    open.FileTypeFilter.Add(".png");
    open.FileTypeFilter.Add(".jpeg");
    open.FileTypeFilter.Add(".jpg");
    StorageFile file = await open.PickSingleFileAsync();
    if (file != null)   
    {
        using (IRandomAccessStream fileStream = await file.OpenAsync(FileAccessMode.Read))
            {
                BitmapImage bitmapImage = new BitmapImage();
                    await bitmapImage.SetSourceAsync(fileStream);
                    fileStream.AsStream().CopyTo(stream);
                    img.Source = bitmapImage;
            }
    }
}

private async void jawabBtn_Click(object sender, RoutedEventArgs e)
{
    Uri urlPath = new Uri("..../essay/test");   
    HttpClient httpClient = new HttpClient();
    httpClient.DefaultRequestHeaders.Add("Authorization",
            string.Format("Bearer {0}", tkn));
    HttpMultipartFormDataContent values = new HttpMultipartFormDataContent();
    values.Add(new HttpStringContent(textValue), "answer");
    values.Add(new HttpStringContent(((App)(App.Current)).SessionID.ToString()), "session");
    values.Add(new HttpStringContent(examstep), "step");
    values.Add(new HttpStringContent(questionId), "question");
    values.Add(new HttpStreamContent(stream.AsInputStream()), "image");
    var response = new HttpResponseMessage();
        try
        {
            response = await httpClient.PostAsync(urlPath, values);
        }
        catch (Exception ex)
        {   
        MessageDialog messageDialog = new MessageDialog(ex.ToString(), "Server Error");
                messageDialog.Commands.Add(new UICommand("OK", (command) =>
                {
            this.Frame.GoBack();
            }));
                await messageDialog.ShowAsync();    
    }
}

I'm having problem like below image when uploading image to server How to handle it?

Answer 1

I've made a simple test about this. Please try to use the IRandomAccessStream directly for your HttpStreamContent. In this way, my code doesn't throw any exception.

Like this:

   fileStream = await file.OpenAsync(FileAccessMode.ReadWrite);

       //... other codes
        HttpClient httpClient = new HttpClient();
        HttpMultipartFormDataContent values = new HttpMultipartFormDataContent();
        //....other codes
        values.Add(new HttpStreamContent(fileStream), "image");
        var response = new HttpResponseMessage();