问题
I'm authenticating with Facebook on my iOS application and use following method to grab the feed. When I check if it is valid JSON object, it returns true, but if I attempt to parse it, it gives me error:
Mistake: The operation couldn’t be completed. (Cocoa error 3840.)
What can be done about that? Here is what is arriving from server, perfectly valid JSON - http://pastebin.com/ZwTnvi5g (got it by NSLog the result).
How do I fix it so the nsjsonserialization parses it correctly?
- (void) refreshButtonPressed
{
FBRequest *request = [[FBRequest alloc] initWithSession:FBSession.activeSession graphPath:@"me/feed"];
[request startWithCompletionHandler:^(FBRequestConnection *connection, id result, NSError *error) {
NSError *mistake;
BOOL can = [NSJSONSerialization isValidJSONObject:result];
NSLog(@"%d", can);
NSDictionary *first = [NSJSONSerialization JSONObjectWithData:result options:NSJSONReadingAllowFragments error:&mistake];
if (mistake) {
NSLog(@"Mistake: %@", [mistake localizedDescription]);
}
}];
}
回答1:
Actually reading documentation could have helped here.
@param result The result of the request. This is a translation of
JSON data to `NSDictionary` and `NSArray` objects. This
is nil if there was an error.
It parses everything itself, I don't even need to do that. So it returns valid NSDictionary or NSArray.
来源：https://stackoverflow.com/questions/17956115/nsjsonserialzation-not-parsing-results-from-facebook-cocoa-error-3840