Develop Reference

How can I get the picture of a Facebook event using server side code?

I'm writing a web app that pulls events data from Facebook, and I can get a lot of the information using an app token, but not the picture, which requires a client token, as documented here: https://developers.facebook.com/docs/graph-api/reference/v2.2/event/picture
I want the code that grabs the event data to run automatically on a server at regular intervals, without requiring a user to log in to their Facebook account.
Is there a way I can get a client token without user intervention? If not, is there another way I can get the event picture?
This is the code I am using to get the event data, using C# and JSON.Net (This gets a list of events created by the specified user - ResortStudios):
var fb = new FacebookClient();
dynamic result = fb.Get( "oauth/access_token", new
{
client_id = "XXXXXXXXXXX",
client_secret = "XXXXXXXXXXXXXXXXXXXXXXXXX",
grant_type = "client_credentials"
} );
var apptoken = result.access_token;
fb = new FacebookClient(apptoken);
result = fb.Get("ResortStudios/events");
JObject events = JObject.Parse(result.ToString());
JArray aEvents = (JArray)events["data"];
string s = aEvents.ToString();
List<fbEvent> lEvents = JsonConvert.DeserializeObject<List<fbEvent>>(s);

I've not tried this but something occurred to me that might work for you. Have you considered something like storing it a non-persistent data store like session state? Then, using the Facebook SDK for .NET, you create an ActionResult for UserInfo, like below. (I know this isn't directly applicable but I hoped it might get you thinking.)
//http://facebooksdk.net/docs/web/ajax-requests/
public ActionResult UserInfo()
{
var accessToken = Session["AccessToken"].ToString();
var client = new FacebookClient(accessToken);
dynamic result = client.Get("me", new { fields = "name,id" });
return Json(new
{
id = result.id,
name = result.name,
});
}

How would you detect the current browser in an Api Controller?

I'm trying to detect the current web browser within one of my Api Controllers in my program using MVC4. Everywhere I look people say to use Request.Browser, however I can't get that to work. Any suggestions or is there something I'm overlooking?

You can use the HttpBrowserCapabilities in System.Web like this
var userAgent = HttpContext.Current.Request.UserAgent;
var userBrowser = new HttpBrowserCapabilities { Capabilities = new Hashtable { { string.Empty, userAgent } } };
var factory = new BrowserCapabilitiesFactory();
factory.ConfigureBrowserCapabilities(new NameValueCollection(), userBrowser);
//Set User browser Properties
BrowserBrand = userBrowser.Browser;
BrowserVersion = userBrowser.Version;
This relies on browscap.ini in Windows/System32/inetsrv/ or Windows/SysWOW64/inetsrv for definitions.
This article may also help - http://stephenwalther.com/archive/2010/03/05/use-asp-net-4-browser-definitions-with-asp-net-3-5

You could do something like following too from within the Web API's action:
System.Net.Http.HttpRequestMessage currentRequest = this.Request;
System.Net.Http.Headers.HttpHeaderValueCollection<System.Net.Http.Headers.ProductInfoHeaderValue> userAgentHeader = currentRequest.Headers.UserAgent;

Custom Like using Facebook C# API

I'm using Facebook C# API and I want to create a custom "Like" action, allowing the user to like objects outside of Facebook.
The user will be allowed to "Like" a custom object, like an Apple or a Book, and the app has to post this information in the user timeline.
I've tried
dynamic res = fb.Post("me/og.likes", new
{
message = "My first like post using Facebook SDK for .NET"
});
But this gives me the following FacebookApiException exception
(Exception - #1611072) The action you're trying to publish is invalid because it does not specify any reference objects. At least one of the following properties must be specified: object.
But if I try
dynamic res = fb.Post("me/og.likes", new
{
object="http://samples.ogp.me/226075010839791"
});
it doesn't even compile, since object is a reserved word on C#.
What should I do?
Is it possible?

Try escape using #:
dynamic res = fb.Post("me/og.likes", new
{
#object="http://samples.ogp.me/226075010839791"
});
EDIT: For other special characters you should be able to use a dictionary instead of a anonymous typed object:
var postInfo = new Dictionary<string, object>();
postInfo.Add("fb:explicitly_shared", "your data");
dynamic res = fb.Post("me/og.likes", postInfo);

Calling node.NiceUrl gives me # in Umbraco

Doing a project in Umbraco, and i've encountered problems in one case that when calling node.NiceUrl I get # as the result. What is weird though is that if i debug it somehow it resolves into the correct url.
var pages = Pages.Select((item, index) => new
{
Url = item.NiceUrl,
Selected = item.Id == currentPage.Id,
Index = index
}).ToList();
Where Pages is obtained from:
CurrentPage.Parent.ChildrenAsList

If I do it this way, it works, but I don't know why.
Url = new Node(item.Id).NiceUrl,

I've encountered this error and it was because the id belonged to a media node.
Media is treated differently to other content and there's no easy way of getting the url because different types of media store the url in different ways depending on context. That's why the NiceUrl function doesn't work for media (according to the umbraco developers).
My specific scenario was using images that had been selected using a media picker. I got the url via the following code. I wrapped it up in an extension method so you can consume it from a template in a convenient way.
public static string GetMediaPropertyUrl(this IPublishedContent thisContent, string alias, UmbracoHelper umbracoHelper = null)
{
string url = "";
if (umbracoHelper == null)
umbracoHelper = new UmbracoHelper(UmbracoContext.Current);
var property = thisContent.GetProperty(alias);
string nodeID = property != null ? property.Value.ToString() : "";
if (!string.IsNullOrWhiteSpace(nodeID))
{
//get the media via the umbraco helper
var media = umbracoHelper.TypedMedia(nodeID);
//if we got the media, return the url property
if (media != null)
url = media.Url;
}
return url;
}

Try like this
Url = umbraco.library.NiceUrl(Item.Id);

How to get the Page Id in my Facebook Application page

I have my application is hosted in FaceBook as a tab and I want to get the page ID when my application is being added to be stored in my logic.
How can I get the page ID, I know it is stored in the URL but when I tried to get it from the page as a server variable, I am not getting it even my application is configured as iFrame ? But this is a standard way to get the parent URL.
C#:
string t= request.serverVariables("HTTP_REFERER");
//doesn't get FB page url even if your app is configured as iframe ?!! #csharpsdk #facebook devs
Any help ?
Thanks a lot.

Here is how I do it:
if (FacebookWebContext.Current.SignedRequest != null)
{
dynamic data = FacebookWebContext.Current.SignedRequest.Data;
if (data.page != null)
{
var pageId = (String)data.page.id;
var isUserAdmin = (Boolean)data.page.admin;
var userLikesPage = (Boolean)data.page.liked;
}
else
{
// not on a page
}
}

The Page ID is not stored in the URL; it is posted to your page within the signed_request form parameter. See this Facebook developer blog post for more details.
You can use the FacebookSignedRequest.Parse method within the Facebook C# SDK to parse the signed request (using your app secret). Once you have done this you can extract the Page ID from the Page JSON object as follows:
string signedRequest = Request.Form["signed_request"];
var DecodedSignedRequest = FacebookSignedRequest.Parse(FacebookContext.Current.AppSecret, SignedRequest);
dynamic SignedRequestData = DecodedSignedRequest.Data;
var RawRequestData = (IDictionary<string, object>)SignedRequestData;
if (RawRequestData.ContainsKey("page") == true)
{
Facebook.JsonObject RawPageData = (Facebook.JsonObject)RawRequestData["page"];
if (RawPageData.ContainsKey("id") == true)
currentFacebookPageID = (string)RawPageData["id"];
}
Hope this helps.

Here's the same solution as Andy Sinclairs's in VB that worked for me:
Dim pageId as Int64 = 0
Dim signed_request As String = Request.Form("signed_request")
Dim req = FacebookSignedRequest.Parse(AppSettings("FacebookSecret"), signed_request)
Dim data As IDictionary(Of String, Object) = req.Data
If data.ContainsKey("page") Then
Dim RawPageData As Facebook.JsonObject = data("page")
If RawPageData.ContainsKey("id") Then
pageId = RawPageData("id")
End If
End If