c# - 如何使用 httpClient.postAsync 在 UWP 中上传图像或 bytes[]

Question

所以我需要上传一张图片到我的 Mysql 数据库以及一些其他字符串，例如名称......我能够将名称添加到 Mysql 数据库中，但我无法为图像添加名称。我将图像转换为一个字节 []，现在我卡住了..这是我使用的代码

private Stream stream = new MemoryStream();
    private CancellationTokenSource cts;

    public MainPage()
    {
        this.InitializeComponent();
    }

    private async void buttonUpload_Click(object sender, RoutedEventArgs e)
    {
        FileOpenPicker open = new FileOpenPicker();
        open.SuggestedStartLocation = PickerLocationId.PicturesLibrary;
        open.ViewMode = PickerViewMode.Thumbnail;

        // Filter to include a sample subset of file types
        open.FileTypeFilter.Clear();
        open.FileTypeFilter.Add(".bmp");
        open.FileTypeFilter.Add(".png");
        open.FileTypeFilter.Add(".jpeg");
        open.FileTypeFilter.Add(".jpg");

        // Open a stream for the selected file
        StorageFile file = await open.PickSingleFileAsync();

        // Ensure a file was selected
        if (file != null)
        {
            // Ensure the stream is disposed once the image is loaded
            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 submit_Click(object sender, RoutedEventArgs e)
    {


        Uri uri = new Uri("http://localhost/mydatabase/add.php");
        HttpClient client = new HttpClient();
        HttpStreamContent streamContent = new HttpStreamContent(stream.AsInputStream());
        HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, uri);
        request.Content = streamContent;
        HttpResponseMessage response = await client.PostAsync(uri, streamContent).AsTask(cts.Token);



    }

Answer 1

试试这个对我有用:

private static async Task Upload(string actionUrl)
{
    Image newImage = Image.FromFile(@"Absolute Path of image");
    ImageConverter _imageConverter = new ImageConverter();
    byte[] paramFileStream= (byte[])_imageConverter.ConvertTo(newImage, typeof(byte[]));

    var formContent = new MultipartFormDataContent
    {
        //send form text values here
        {new StringContent("value1"), "key1"},
        {new StringContent("value2"), "key2" },
        // send Image Here
        {new StreamContent(new MemoryStream(paramFileStream)), "imagekey", "filename.jpg"}
    };

    var myHttpClient = new HttpClient();
    var response = await myHttpClient.PostAsync(actionUrl.ToString(), formContent);
    string stringContent = await response.Content.ReadAsStringAsync();

    return response;
}