ios - 从youtube API v3响应中提取标题

Question

如何从youtube API调用的响应中提取title。

以下是获取YouTube视频详情的代码。

- (void)getVideoTitle{
    // Set up your URL
    NSString *youtubeApi = @"https://www.googleapis.com/youtube/v3/videos?part=contentDetails%2C+snippet%2C+statistics&id=zB4I68XVPzQ&key=API_KEY";
    NSURL *url = [[NSURL alloc] initWithString:youtubeApi];

    // Create your request
    NSURLRequest *request = [NSURLRequest requestWithURL:url];

    // Send the request asynchronously
    [[[NSURLSession sharedSession] dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *connectionError) {

        // Callback, parse the data and check for errors
        if (data && !connectionError) {
            NSError *jsonError;
            NSDictionary *jsonResult = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:&jsonError];

            if (!jsonError) {
                NSLog(@"Response from YouTube: %@", jsonResult);
            }
        }
    }] resume];


}
@end

这是回复。

Response from YouTube: {
    etag = "\"m2yskBQFythfE4irbTIeOgYYfBU/3w7VzHWX6Z741beZqAzUx-AoGQQ\"";
    items =     (
                {
            contentDetails =             {
                caption = false;
                definition = hd;
                dimension = 2d;
                duration = PT2M13S;
                licensedContent = 1;
                projection = rectangular;
            };
            etag = "\"m2yskBQFythfE4irbTIeOgYYfBU/riulsg6pv-HCB96fEN7edGYXYGg\"";
            id = zB4I68XVPzQ;
            kind = "youtube#video";
            snippet =             {
                categoryId = 24;
                channelId = "UCZGYJFUizSax-yElQaFDp5Q";
                channelTitle = "Star Wars";
                defaultAudioLanguage = en;
                description = "Star Wars: The Last Jedi. Arriving in your galaxy December 15.\n\nVisit Star Wars at http://www.starwars.com\nSubscribe to Star Wars on YouTube at http://www.youtube.com/starwars\nLike Star Wars on Facebook at http://www.facebook.com/starwars\nFollow Star Wars on Twitter at http://www.twitter.com/starwars\nFollow Star Wars on Instagram at http://www.instagram.com/starwars\nFollow Star Wars on Tumblr at http://starwars.tumblr.com/";
                liveBroadcastContent = none;
                localized =                 {
                    description = "Star Wars: The Last Jedi. Arriving in your galaxy December 15.\n\nVisit Star Wars at http://www.starwars.com\nSubscribe to Star Wars on YouTube at http://www.youtube.com/starwars\nLike Star Wars on Facebook at http://www.facebook.com/starwars\nFollow Star Wars on Twitter at http://www.twitter.com/starwars\nFollow Star Wars on Instagram at http://www.instagram.com/starwars\nFollow Star Wars on Tumblr at http://starwars.tumblr.com/";
                    title = "Star Wars: The Last Jedi Official Teaser";
                };
                publishedAt = "2017-04-14T15:56:13.000Z";
                tags =                 (
                    "star wars",
                    "the last jedi",
                    "daisy ridley",
                    "mark hamill",
                    "adam driver",
                    rey,
                    "kylo ren",
                    "luke skywalker",
                    lucasfilm,
                    trailer
                );
                thumbnails =                 {
                    default =                     {
                        height = 90;
                        url = "https://i.ytimg.com/vi/zB4I68XVPzQ/default.jpg";
                        width = 120;
                    };
                    high =                     {
                        height = 360;
                        url = "https://i.ytimg.com/vi/zB4I68XVPzQ/hqdefault.jpg";
                        width = 480;
                    };
                    maxres =                     {
                        height = 720;
                        url = "https://i.ytimg.com/vi/zB4I68XVPzQ/maxresdefault.jpg";
                        width = 1280;
                    };
                    medium =                     {
                        height = 180;
                        url = "https://i.ytimg.com/vi/zB4I68XVPzQ/mqdefault.jpg";
                        width = 320;
                    };
                    standard =                     {
                        height = 480;
                        url = "https://i.ytimg.com/vi/zB4I68XVPzQ/sddefault.jpg";
                        width = 640;
                    };
                };
                title = "Star Wars: The Last Jedi Official Teaser";
            };
            statistics =             {
                commentCount = 54170;
                dislikeCount = 10550;
                favoriteCount = 0;
                likeCount = 341919;
                viewCount = 14611544;
            };
        }
    );
    kind = "youtube#videoListResponse";
    pageInfo =     {
        resultsPerPage = 1;
        totalResults = 1;
    };
}

Answer 1

不确定这在目标C中如何起作用，但在swift中它将如下

if let dictionary = jsonResult as? NSDictionary {
    if let itemArray = dictionary["items"] as? NSArray {
        if let item = itemArray[0] as? NSDictionary {
            if let snippet = item["snippet"] as? NSDictionary {
                if let title = snippet["title"] as? String {
                    print(title)
                }
            }
        }
    }
}