public void Share_Score(){
        FB.Feed (
            toId: "",
            link: "http://www.facebook.com/appname",
            linkName: "App Name",
            linkCaption: "I just scored " + " points",
            linkDescription: "Playing this game is awesome!",
            actionLink:"http://www.facebook.com/appname",
            actionName: "Appname Fan Page"
                );
    }

link: "http://apps.facebook.com/" + FB.AppId + "/?challenge_brag" + (FB.IsLoggedIn ? FB.UserId : "guest")