Question

Imgur is a image uploading website who offers an API to upload

My code looks exactly like the PHP code they provide as an example. however, in their php code they are http_build_query($pvars);

It seems like they are URLEncoding their query before posting it. edit: Note that I have changed to full .NET 3.5 rather then the client profile. This gave me access to system.web so I used httputliity.urlencode(). This made the api return a “fail” with a “no image was sent”. If I don’t encode then the API returns an “okay” with a link to the picture, however no picture is uploaded (like a blank file).

How can I fix my code to work properly against their API?

 Image image = Image.FromFile("C:\\Users\\Affan\\Pictures\\1509310.jpg");
        MemoryStream ms = new MemoryStream();
        // Convert Image to byte[]
        image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
        byte[] imageBytes = ms.ToArray();

        WebRequest wb = WebRequest.Create(new Uri("http://imgur.com/api/upload.xml"));
        wb.ContentType = "application/x-www-form-urlencoded";            
        wb.Method = "POST";
        wb.Timeout = 10000;
        Console.WriteLine(imageBytes.Length);
        string parameters = "key=433a1bf4743dd8d7845629b95b5ca1b4&image=" + Convert.ToBase64String(imageBytes);


        Console.WriteLine("parameters: " + parameters.Length);
        System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
        byte[] bytes = encoding.GetBytes(parameters);
        // byte[] bytes = Convert.FromBase64String(parameters);

        System.IO.Stream os = null;
        try { // send the Post
            wb.ContentLength = bytes.Length;   //Count bytes to send
            os = wb.GetRequestStream();               
            os.Write(bytes, 0, bytes.Length);         //Send it
        } catch (WebException ex) {
            MessageBox.Show(ex.Message, "HttpPost: Request error");
            Console.WriteLine(ex.Message);
        } finally {
            if (os != null) {
               // os.Close();
            }
        }

        try { // get the response
            WebResponse webResponse = wb.GetResponse();

            StreamReader sr = new StreamReader(webResponse.GetResponseStream());
            //MessageBox.Show(sr.ReadToEnd().Trim());
            Console.WriteLine(sr.ReadToEnd().Trim());
        } catch (WebException ex) {
            MessageBox.Show(ex.Message, "HttpPost: Response error");
        }       

Answer 1

I’ve just uploaded this image

using this code:

using (var w = new WebClient())
{
    var values = new NameValueCollection
    {
        { "key", "433a1bf4743dd8d7845629b95b5ca1b4" },
        { "image", Convert.ToBase64String(File.ReadAllBytes(@"hello.png")) }
    };

    byte[] response = w.UploadValues("http://imgur.com/api/upload.xml", values);

    Console.WriteLine(XDocument.Load(new MemoryStream(response)));
}

You might want to change your API key now 🙂

The output was:

<rsp stat="ok">
  <image_hash>IWg2O</image_hash>
  <delete_hash>fQAXiR2Fdq</delete_hash>
  <original_image>http://i.imgur.com/IWg2O.png</original_image>
  <large_thumbnail>http://i.imgur.com/IWg2Ol.jpg</large_thumbnail>
  <small_thumbnail>http://i.imgur.com/IWg2Os.jpg</small_thumbnail>
  <imgur_page>http://imgur.com/IWg2O</imgur_page>
  <delete_page>http://imgur.com/delete/fQAXiR2Fdq</delete_page>
</rsp>