public FacebookContextSettings()
{
FacebookWebContext facebookContext = FacebookWebContext.Current;
IFacebookApplication settings;
FacebookSignedRequest signedRequest;
if (facebookContext.SignedRequest == null)
{
// ajax requests won't have a signed request, so we need to build it from the current http request
// see http://facebooksdk.codeplex.com/discussions/251878
settings = FacebookApplication.Current;
try
{
signedRequest = FacebookSignedRequest.Parse(settings, SignedRequest);
}
catch (Exception exception)
{
// Facebook posts to the iframe, but only IE supports this so the first request will always fail for non IE browsers
if (HttpContext.Current.Request.Browser.Browser.Contains("IE"))
{
throw;
}
// it doesn't break anything so we'll throw a custom exception so that we can filter it out later
InvalidSignedRequestException signedRequestException =
new InvalidSignedRequestException("Invalid SignedRequest - Non - IE (" + SignedRequest + ")", exception);
throw signedRequestException;
}
}
else
{
settings = facebookContext.Settings;
signedRequest = facebookContext.SignedRequest;
}
CanvasPage = settings.CanvasPage;
AccessToken = signedRequest.AccessToken;
AppId = settings.AppId;
UserId = signedRequest.UserId;
}
private FacebookSignedRequest ParseSignedRequest(IFacebookApplication settings)
{
HttpContext context = HttpContext.Current;
if (context != null)
{
HttpContextWrapper contextWrapper = new HttpContextWrapper(context);
if (contextWrapper.Request.IsAjaxRequest())
{
// ajax requests won't have a signed request, so we need to build it from the current http request
// see http://facebooksdk.codeplex.com/discussions/251878
try
{
return(FacebookSignedRequest.Parse(settings, SignedRequest));
}
catch (Exception exception)
{
// Facebook posts to the iframe, but only IE supports this so the first request will always fail for non IE browsers
if (context.Request.Browser.Browser.Contains("IE"))
{
throw;
}
// it doesn't break anything so we'll throw a custom exception so that we can filter it out later
InvalidSignedRequestException signedRequestException =
new InvalidSignedRequestException(
"Invalid SignedRequest - Non - IE (" + SignedRequest + ")",
exception);
throw signedRequestException;
}
}
}
return(null);
}