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Post message with Facebook SDK .NET

I have created a facebook page and a facebook application for my website and now I need to post messages onto the facebook page with help of facebook SDK .NET.
This is what I got so far :
public static bool UploadPost(string message)
{
dynamic result;
//https://developers.facebook.com/tools/explorer/
//https://developers.facebook.com/tools/access_token/
FacebookClient client = new FacebookClient("secret access token");
result = client.Get("oauth/access_token", new
{
client_id = "[Client ID number]",
client_secret = "[Client sercret",
grant_type = "client_credentials",
});
result = client.Post("[facebook app Id]/feed", new { message = "Test Message from app" });
//result.id;
result = client.Get("[facebook app Id]");
return false;
}
When running this I get : Additional information: (OAuthException - #200) (#200) The user hasn't authorized the application to perform this action on client.Post. If I remove the client.Post row every thing works good, the correct data is fetched.
I have tried follow some helps on facebook SDK .NET website but it is still not working.
The main problem now is that I get permission exception. I was hoping that my facebook app hade enouth permissions to publish post from my website to the facebook page.

Here is a step wise tutorial to register your application with facebook and get an app Id for your application.
Then for permissions ::
private const string ExtendedPermissions = "user_about_me,read_stream,publish_stream";
This is a string of permissions. Pass it on further for getting correct permissions to post messages on page. Post using your standard code for posting no FB pages.
Cheers. Hope it helps.

Are you trying to post to [facebook app id]?
I would recomend to post to "me/feed" and test if that works.
Also, to post to Facebook you have to have the publish_stream permission
private async Task Authenticate()
{
string message = String.Empty;
try
{
session = await App.FacebookSessionClient.LoginAsync("user_about_me,read_stream,publish_actions");
App.AccessToken = session.AccessToken;
App.FacebookId = session.FacebookId;
Dispatcher.BeginInvoke(() => NavigationService.Navigate(new Uri("/Pages/LandingPage.xaml", UriKind.Relative)));
}
catch (InvalidOperationException e)
{
message = "Login failed! Exception details: " + e.Message;
MessageBox.Show(message);
}
}
Should work :)

The following should work.
var fb = new FacebookClient("access_token");
fb.PostCompleted += (o, e) => {
if(e.Error == null) {
var result = (IDictionary<string, object>)e.GetResultData();
var newPostId = (string)result.id;
}
};
var parameters = new Dictionary<string, object>();
parameters["message"] = "My first wall post using Facebook SDK for .NET";
fb.PostAsync("me/feed", parameters);
This was taken directly from the documentation.

By creating a extended page token and use it to make the post everything works just fine. See this : How to get Page Access Token by code?
Im surprised that this simple task was so hard to get running and that there was vary little help to get.

PayPal Express Checkout SOAP API: Refunds

I use the PayPal Express Checkout SOAP service. For example here's a trimmed down version of the code to redirect the user to PayPal Sandbox when checking out:
var client = new PayPalAPIAAInterfaceClient();
var credentials = new CustomSecurityHeaderType() {
Credentials = new UserIdPasswordType() { ... }
};
var paymentDetails = new PaymentDetailsType() {
OrderTotal = new BasicAmountType() {
Value = string.Format("{0:0.00}", 100m)
}
};
var request = new SetExpressCheckoutReq() {
SetExpressCheckoutRequest = new SetExpressCheckoutRequestType() {
SetExpressCheckoutRequestDetails = new SetExpressCheckoutRequestDetailsType() {
PaymentDetails = new PaymentDetailsType[] { paymentDetails },
CancelURL = "http://www.mysite.com" + Url.Action("Cancelled", "PayPalCheckout"),
ReturnURL = "http://www.mysite.com" + Url.Action("Index", "PayPalCheckout")
},
Version = "60.0"
}
};
var response = client.SetExpressCheckout(ref credentials, request);
return Redirect(string.Format("{0}?cmd=_express-checkout&token={1}", "https://www.sandbox.paypal.com/cgi-bin/webscr", response.Token));
I then handle the data when the user is returned to the ReturnUrl. This was taken from some code I found on another website.
I now need to add a refund facility to my site. I was wondering if anyone else has done this? I've tried searching online but can't seem to find anything that helps. I also tried doing it myself but the API isn't very intuitive.
I'd appreciate the help. Thanks

It would just need to be a RefundTransaction API call that you would need to execute. Are you trying to have your return page issue a refund based on a condition, or are you trying to create a GUI type of interface to allow someone to issue a refund for a transaction? Have you looked at the code samples for this within the SDK's that PayPal offers? You should be able to use this code.

Google plus language programming using people.list

as a new researcher I am trying to get information about relations among people on G+. I want to get other's circle list for some research purpose. It seems that the G+ API offers a web version to use people.list with a OAuth2 token. My question is, does people.list support programming language such as c#, java? I tried with c# but it seems to be blocked by the server.
Is there is a way to apply people.list in c#,java etc? If yes, are there some samples? Or someone provide some open codes to fullfill similar functions?
thanks very much.
the following is my related c# code:
var provider = new NativeApplicationClient(GoogleAuthenticationServer.Description)
{
ClientIdentifier = credentials.ClientId,
ClientSecret = credentials.ClientSecret
};
var auth = new OAuth2Authenticator<NativeApplicationClient>(provider, GetAuthorization);
var servicelist = new PlusService(new BaseClientService.Initializer()
{
Authenticator = auth
});
string userId = "********************";
PeopleResource.ListRequest circle = servicelist.People.List(userId, new PeopleResource.Collection());
circle.MaxResults = 5;
PeopleFeed danielfeed = circle.Fetch();
private static IAuthorizationState GetAuthorization(NativeApplicationClient arg)
{
IAuthorizationState state = new AuthorizationState(new[] { TasksService.Scopes.Tasks.GetStringValue() });
state.Callback = new Uri(NativeApplicationClient.OutOfBandCallbackUrl);
Uri authUri = arg.RequestUserAuthorization(state);
Process.Start(authUri.ToString());
Console.Write(" Authorization Code: ");
string authCode = Console.ReadLine();
Console.WriteLine();
return arg.ProcessUserAuthorization(authCode, state);
}
}
The program goes wrong at "PeopleFeed danielfeed = circle.Fetch();" I think I have already passed the OAuth token to the people.list function by variable "auth". Can you give me some advices?

Google's People:list API's documentation is here. The entire API is RESTful, and does not block any language.
You can use C#, and just need to learn how to consume a REST API in C#. The C# class you will want to use is the HttpClient class. It is very well documented here and there are plenty of tutorials online, as well as here on SO.

(OAuthException) An active access token must be used to query information about the current user

I'm using Facebook C# sdk with the code,
i'm trying to create a new score for a user
but i get this error:
(OAuthException) An active access token must be used to query information about the current user.
what am i missing?
protected void btnAddScore_Click(object sender, EventArgs e)
{
if (CanvasAuthorizer.Authorize())
{
var fb = new FacebookWebClient();
dynamic parameters = new ExpandoObject();
parameters.score = 77;
parameters.access_token = GetAppAccessToken();
try
{
dynamic id = fb.Post("me/scores", parameters);
lblPostMessageResult.Text = "Message posted successfully";
txtMessage.Text = string.Empty;
}
catch (FacebookApiException ex)
{
lblPostMessageResult.Text = ex.Message;
}
}
}
private string GetAppAccessToken()
{
var oauthClient = new FacebookOAuthClient
{
AppId = FacebookWebContext.Current.Settings.AppId,
AppSecret = FacebookWebContext.Current.Settings.AppSecret
};
dynamic result = oauthClient.GetApplicationAccessToken();
string appAccessToken = result.access_token;
return appAccessToken;
}
edit:
I got the answer form here:
http://facebooksdk.codeplex.com/discussions/279307
the new right code is:
if (CanvasAuthorizer.Authorize())
{
var fb = new FacebookClient(CanvasAuthorizer.FacebookWebRequest.AccessToken);
var oauthClient = new FacebookOAuthClient(FacebookApplication.Current);
dynamic parameters = new ExpandoObject();
parameters.score = 100;
dynamic ac = oauthClient.GetApplicationAccessToken();
parameters.access_token = ac.access_token;
dynamic result = fb.Post(CanvasAuthorizer.FacebookWebRequest.UserId + "/scores", parameters);
}

Answer:-
Actually for using SCORE Graph API you need the "Application access token" which is different than a normal access token
So if you want your task to be done GET an Application access token by using the following script.......
And then replace the generated application_access_token with old access_token, that's it
The below code is written in php try convert it in c# and then apply it
$APPLICATION_ID = "APP_ID";
$APPLICATION_SECRET = "APP_SECRET";
$token_url = "https://graph.facebook.com/oauth/access_token?" .
"client_id=" . $APPLICATION_ID .
"&client_secret=" . $APPLICATION_SECRET .
"&grant_type=client_credentials";
$app_token = file_get_contents($token_url);
After getting this application access token you can easily do this task.
When You Need An Application Access Token
You need to use a Facebook application access token when you have a process that acts on behalf of the application, rather than on behalf of a particular user. This happens when you access your Facebook Insights data for your app via the graph, and also when you want to create test Facebook users for your app.
Sadly, the documentation for this is buried in the authentication guide for the Facebook graph API.

Your application need to take "publish_actions" permission from user to update the score.
Refer to Create or update a score for a user section of the below documentation.
https://developers.facebook.com/docs/score/

Google+ API: How can I use RefreshTokens to avoid requesting access every time my app launches?

I'm trying to use the Google+ API to access info for the authenticated user. I've copied some code from one of the samples, which works fine (below), however I'm having trouble making it work in a way I can reuse the token across app-launches.
I tried capturing the "RefreshToken" property and using provider.RefreshToken() (amongst other things) and always get a 400 Bad Request response.
Does anyone know how to make this work, or know where I can find some samples? The Google Code site doesn't seem to cover this :-(
class Program
{
private const string Scope = "https://www.googleapis.com/auth/plus.me";
static void Main(string[] args)
{
var provider = new NativeApplicationClient(GoogleAuthenticationServer.Description);
provider.ClientIdentifier = "BLAH";
provider.ClientSecret = "BLAH";
var auth = new OAuth2Authenticator<NativeApplicationClient>(provider, GetAuthentication);
var plus = new PlusService(auth);
plus.Key = "BLAH";
var me = plus.People.Get("me").Fetch();
Console.WriteLine(me.DisplayName);
}
private static IAuthorizationState GetAuthentication(NativeApplicationClient arg)
{
// Get the auth URL:
IAuthorizationState state = new AuthorizationState(new[] { Scope });
state.Callback = new Uri(NativeApplicationClient.OutOfBandCallbackUrl);
Uri authUri = arg.RequestUserAuthorization(state);
// Request authorization from the user (by opening a browser window):
Process.Start(authUri.ToString());
Console.Write(" Authorization Code: ");
string authCode = Console.ReadLine();
Console.WriteLine();
// Retrieve the access token by using the authorization code:
return arg.ProcessUserAuthorization(authCode, state);
}
}

Here is an example. Make sure you add a string setting called RefreshToken and reference System.Security or find another way to safely store the refresh token.
private static byte[] aditionalEntropy = { 1, 2, 3, 4, 5 };
private static IAuthorizationState GetAuthorization(NativeApplicationClient arg)
{
// Get the auth URL:
IAuthorizationState state = new AuthorizationState(new[] { PlusService.Scopes.PlusMe.GetStringValue() });
state.Callback = new Uri(NativeApplicationClient.OutOfBandCallbackUrl);
string refreshToken = LoadRefreshToken();
if (!String.IsNullOrWhiteSpace(refreshToken))
{
state.RefreshToken = refreshToken;
if (arg.RefreshToken(state))
return state;
}
Uri authUri = arg.RequestUserAuthorization(state);
// Request authorization from the user (by opening a browser window):
Process.Start(authUri.ToString());
Console.Write(" Authorization Code: ");
string authCode = Console.ReadLine();
Console.WriteLine();
// Retrieve the access token by using the authorization code:
var result = arg.ProcessUserAuthorization(authCode, state);
StoreRefreshToken(state);
return result;
}
private static string LoadRefreshToken()
{
return Encoding.Unicode.GetString(ProtectedData.Unprotect(Convert.FromBase64String(Properties.Settings.Default.RefreshToken), aditionalEntropy, DataProtectionScope.CurrentUser));
}
private static void StoreRefreshToken(IAuthorizationState state)
{
Properties.Settings.Default.RefreshToken = Convert.ToBase64String(ProtectedData.Protect(Encoding.Unicode.GetBytes(state.RefreshToken), aditionalEntropy, DataProtectionScope.CurrentUser));
Properties.Settings.Default.Save();
}

The general idea is as follows:
You redirect the user to Google's Authorization Endpoint.
You obtain a short-lived Authorization Code.
You immediately exchange the Authorization Code for a long-lived Access Token using Google's Token Endpoint. The Access Token comes with an expiry date and a Refresh Token.
You make requests to Google's API using the Access Token.
You can reuse the Access Token for as many requests as you like until it expires. Then you can use the Refresh Token to request a new Access Token (which comes with a new expiry date and a new Refresh Token).
See also:
The OAuth 2.0 Authorization Protocol
Google's OAuth 2.0 documentation

I also had problems with getting "offline" authentication to work (i.e. acquiring authentication with a refresh token), and got HTTP-response 400 Bad request with a code similar to the OP's code. However, I got it to work with the line client.ClientCredentialApplicator = ClientCredentialApplicator.PostParameter(this.clientSecret); in the Authenticate-method. This is essential to get a working code -- I think this line forces the clientSecret to be sent as a POST-parameter to the server (instead of as a HTTP Basic Auth-parameter).
This solution assumes that you've already got a client ID, a client secret and a refresh-token. Note that you don't need to enter an access-token in the code. (A short-lived access-code is acquired "under the hood" from the Google server when sending the long-lived refresh-token with the line client.RefreshAuthorization(state);. This access-token is stored as part of the auth-variable, from where it is used to authorize the API-calls "under the hood".)
A code example that works for me with Google API v3 for accessing my Google Calendar:
class SomeClass
{
private string clientID = "XXXXXXXXX.apps.googleusercontent.com";
private string clientSecret = "MY_CLIENT_SECRET";
private string refreshToken = "MY_REFRESH_TOKEN";
private string primaryCal = "MY_GMAIL_ADDRESS";
private void button2_Click_1(object sender, EventArgs e)
{
try
{
NativeApplicationClient client = new NativeApplicationClient(GoogleAuthenticationServer.Description, this.clientID, this.clientSecret);
OAuth2Authenticator<NativeApplicationClient> auth = new OAuth2Authenticator<NativeApplicationClient>(client, Authenticate);
// Authenticated and ready for API calls...
// EITHER Calendar API calls (tested):
CalendarService cal = new CalendarService(auth);
EventsResource.ListRequest listrequest = cal.Events.List(this.primaryCal);
Google.Apis.Calendar.v3.Data.Events events = listrequest.Fetch();
// iterate the events and show them here.
// OR Plus API calls (not tested) - copied from OP's code:
var plus = new PlusService(auth);
plus.Key = "BLAH"; // don't know what this line does.
var me = plus.People.Get("me").Fetch();
Console.WriteLine(me.DisplayName);
// OR some other API calls...
}
catch (Exception ex)
{
Console.WriteLine("Error while communicating with Google servers. Try again(?). The error was:\r\n" + ex.Message + "\r\n\r\nInner exception:\r\n" + ex.InnerException.Message);
}
}
private IAuthorizationState Authenticate(NativeApplicationClient client)
{
IAuthorizationState state = new AuthorizationState(new string[] { }) { RefreshToken = this.refreshToken };
// IMPORTANT - does not work without:
client.ClientCredentialApplicator = ClientCredentialApplicator.PostParameter(this.clientSecret);
client.RefreshAuthorization(state);
return state;
}
}

The OAuth 2.0 spec is not yet finished, and there is a smattering of spec implementations out there across the various clients and services that cause these errors to appear. Mostly likely you're doing everything right, but the DotNetOpenAuth version you're using implements a different draft of OAuth 2.0 than Google is currently implementing. Neither part is "right", since the spec isn't yet finalized, but it makes compatibility something of a nightmare.
You can check that the DotNetOpenAuth version you're using is the latest (in case that helps, which it might), but ultimately you may need to either sit tight until the specs are finalized and everyone implements them correctly, or read the Google docs yourself (which presumably describe their version of OAuth 2.0) and implement one that specifically targets their draft version.

I would recommend looking at the "SampleHelper" project in the Samples solution of the Google .NET Client API:
Samples/SampleHelper/AuthorizationMgr.cs
This file shows both how to use Windows Protected Data to store a Refresh token, and it also shows how to use a Local Loopback Server and different techniques to capture the Access code instead of having the user enter it manually.
One of the samples in the library which use this method of authorization can be found below:
Samples/Tasks.CreateTasks/Program.cs