Question

I’m trying to post a photo to Facebook using Graph API. I have managed to post a message to my timeline, but not a photo. The Facebook-debugger gives no errors and the object properties are correct.

public class oAuthFacebook
{
    public enum Method { GET, POST };

    public const string AUTHORIZE = "https://graph.facebook.com/oauth/authorize";

    public const string ACCESS_TOKEN = "https://graph.facebook.com/oauth/access_token";

    public const string CALLBACK_URL ="http://test.com/FbCallback.aspx";


    private string _consumerKey = "";

    private string _consumerSecret = "";

    private string _token = "";



 public string ConsumerKey
{

    get
    {
        if (_consumerKey.Length == 0)
        {
            _consumerKey = "";
        }
        return _consumerKey;
    }
    set { _consumerKey = value; }
}


public string ConsumerSecret 
{
    get
    {
        if (_consumerSecret.Length == 0)
        {
            _consumerSecret = "";
        }
        return _consumerSecret;
    }
    set { _consumerSecret = value; }

    }

public string Token { get { return _token; } set { _token = value; } }





public string AuthorizationLinkGet()
{
    return string.Format("{0}?client_id={1}&redirect_uri={2}&,publish_actions",
  AUTHORIZE, this.ConsumerKey, CALLBACK_URL);
}

public void AccessTokenGet(string authToken)
{
    this.Token = authToken;
    string accessTokenUrl = string.Format("{0}?client_id={1}&redirect_uri=
  {2}&client_secret={3}&code={4}",
    ACCESS_TOKEN, this.ConsumerKey, CALLBACK_URL, this.ConsumerSecret, authToken);

    string response = WebRequest(Method.GET, accessTokenUrl, String.Empty);

    if (response.Length > 0)
    {
        NameValueCollection qs = HttpUtility.ParseQueryString(response);

        if (qs["access_token"] != null)
        {
            this.Token = qs["access_token"];
        }
    }
}

public string WebRequest(Method method, string url, string postData)
{
    HttpWebRequest webRequest = null;
    StreamWriter requestWriter = null;
    string responseData = "";
    webRequest = System.Net.WebRequest.Create(url) as HttpWebRequest;
    webRequest.Method = method.ToString();
    webRequest.ServicePoint.Expect100Continue = false;
    webRequest.UserAgent = "http://test.com";
    webRequest.Timeout = 40000;

    if (method == Method.POST)
    {
        webRequest.ContentType = "application/x-www-form-urlencoded";

        requestWriter = new StreamWriter(webRequest.GetRequestStream());
        try
        {
            requestWriter.Write(postData);
        }
        catch
        {
            throw;
        }
        finally
        {
            requestWriter.Close();
            requestWriter = null;
        }
    }
    responseData = WebResponseGet(webRequest);
    webRequest = null;
    return responseData;
}



public string WebResponseGet(HttpWebRequest webRequest)
{
    StreamReader responseReader = null;
    string responseData = "";
    try
    {
        responseReader = new StreamReader(webRequest.GetResponse().GetResponseStream());
        responseData = responseReader.ReadToEnd();
    }
    catch
    {
        throw;
    }
    finally
    {
        webRequest.GetResponse().GetResponseStream().Close();
        responseReader.Close();
        responseReader = null;
    }
    return responseData;
}

And this is how I sent a testmessage, it works fine:

var json = oAuth.WebRequest(oAuthFacebook.Method.POST, url, "message=" +
HttpUtility.UrlEncode("Testmessage"));

I’ve tried for days to get it to work with a photo instead, any ideas of what I’m doing wrong?

Answer 1

I can suggest to look at FB C# SDK (available here or in NuGet) instead of sending raw requests. Here is my function I use to upload images to FB album (you should either know album ID or you can create it as well, or you can enumerate all the albums and get the one you need):

public static string UploadPhoto(string imageName, string albumID, string accesstoken, string photoComment = null, bool doNotPostStory = false)
{
    var fbAPI = new FacebookApp(accesstoken);
    var p = new FacebookMediaObject {FileName = path};

    p.SetValue( <<YOUR IMAGE GOES HERE AS byte[]>>);

    p.ContentType = "multipart/form-data";

    var param = new Dictionary<string, object> { {"attachment", p} };
    if (!string.IsNullOrEmpty(photoComment))
        param.Add("message", photoComment);

    // http://stackoverflow.com/questions/7340949/is-it-possible-to-upload-a-photo-to-fanpage-album-without-publishing-it
    // http://developers.facebook.com/blog/post/482/
    if (doNotPostStory == true)
    {
        param.Add("no_story", "1");
    }

    var result = fbAPI.Post(string.Format("http://graph.facebook.com/{0}/photos", albumID), param);
    return result.ToString();
}