Question

How to add an application to a page(which I have created) through API with Publish_stream permissions?

Here is the Sequence of things I have tried sofar using app.
Adding App to a page using page access token code is adding app to page apps section but unable to add “publish_stream,manage_pages” permission.

For log in to Facebook

private const string Scope = "publish_stream,manage_pages";
   FacebookClient _fb = new FacebookClient();
   var fbLoginUrl = _fb.GetLoginUrl(
                new
                {
                    client_id = AppId,
                    client_secret = Appsecret,
                    redirect_uri = RedirectUri,
                    response_type = "code",
                    scope = Scope,
                    state = state
                });

To get short lived access token

if (Request.QueryString["code"] != null)
            code = Request.QueryString["code"];
           var result = _fb.Post("oauth/access_token",
                                  new
                                  {
                                      client_id = AppId,
                                      client_secret = Appsecret,
                                      redirect_uri = RedirectUri,
                                      code = code,
                                      scope = Scope,
                                      response_type="token"
                                  });

To get long lived access token

var result1 = _fb.Post(“oauth/access_token”,
new
{
client_id = AppId,
client_secret = Appsecret,
grant_type = “fb_exchange_token”,
fb_exchange_token= Session[“fb_access_token”] as string
});

To get Page access Token

dynamic accounts = _fb.Get("me/accounts");

Add App to a Page using Page Access Token

var sResult = _fb.Post("<PAGE-ID>/tabs",
                                                    new
                                                    {
                                                        app_id = AppId,
                                                        access_token = <PAGE ACCESS TOKEN>,
                                                        scope = Scope
                                                    });

Answer 1

It seems from your comments you’re trying to post ‘as’ the app onto a page – this is not possible. You need to post using a page access token retrieved from an admin of the page, and this page access token allows you to make posts on behalf of the page. Apps cannot post ‘as themselves’.