Question

我有一个json字符串items，即

{
 "items": [
  {
   "kind": "youtube#playlistItem",
   "etag": "\"uQc-MPTsstrHkWLmeNsM/NAYVM2gp_1c4XbQ9zYswb1-_gnk\"",
   "id": "UExGS2IhV2ZJM2tZMTg2MWZZeDR2cS41NEM3RjdGQ0FDRjkwNUQ5",
   "snippet": {
    "publishedAt": "2017-03-21T20:38:22.000Z",
    "channelId": "UCRUNoQu8kdtsY94D9MZ_sXA",
    "title": "News Plus 21-03-17",
    "description": "News Plus 21-03-17",
    "thumbnails": {
     "default": {
      "url": "https://i.ytimg.com/vi/FIXv7nmU/default.jpg",
      "width": 120,
      "height": 90
     },
     "medium": {
      "url": "https://i.ytimg.com/vi/FFynmU/mqdefault.jpg",
      "width": 320,
      "height": 180
     },
     "high": {
      "url": "https://i.ytimg.com/vi/FIXvnmU/hqdefault.jpg",
      "width": 480,
      "height": 360
     }
    },
    "channelTitle": "",
    "playlistId": "PLFKb5r-iLUmbOhkY1861fYx4vq",
    "position": 0,
    "resourceId": {
     "kind": "youtube#video",
     "videoId": "FIXvFylfjwmU"
    }
   }
  },
  {
   "kind": "youtube#playlistItem",
   "etag": "\"uQc-MPTsstrHkeNsM/TKjx1_sGvJVB3tX8cFnxsE\"",
   "id": "UExGS2I1ci1pTFVtYk9oc2htryhjrtUNBMTM5RDMyREQ5",
   "snippet": {
    "publishedAt": "2017-03-21T19:34:48.000Z",
    "channelId": "UCtsY94D9MZ_sXA",
    "title": "Private video",
    "description": "This video is private.",
    "channelTitle": "Capital TV",
    "playlistId": "PLFKb5r-iLUmbOh861fYx4vq",
    "position": 1,
    "resourceId": {
     "kind": "youtube#video",
     "videoId": "VQ1rDS59318"
    }
   }
  },
  {
   "kind": "youtube#playlistItem",
   "etag": "\"uQc-MPTsstrHkWLmeNsM/JXH9kcF8my3r2Yl0OPK3U\"",
   "id": "UExGS2I1ci1pTFVtYhV2ZJM2tZMTg2MWZZeDR2BBNzZCQzY5MDk4",
   "snippet": {
    "publishedAt": "2017-03-21T19:06:41.000Z",
    "channelId": "UCRUNtrhjsY94D9MZ_sXA",
    "title": "Director NAB Corruption Scandal",
    "description": "",
    "thumbnails": {
     "default": {
      "url": "https://i.ytimg.com/vi/BCnejgyQ/default.jpg",
      "width": 120,
      "height": 90
     },
     "medium": {
      "url": "https://i.ytimg.com/vi/BCnejyQ/mqdefault.jpg",
      "width": 320,
      "height": 180
     },
     "high": {
      "url": "https://i.ytimg.com/vi/BCneyQ/hqdault.jpg",
      "width": 480,
      "height": 360
     }
    },
    "channelTitle": "Capital TV",
    "playlistId": "PLFKb5r-iLUmbOhkY1861fYx4vq",
    "position": 2,
    "resourceId": {
     "kind": "youtube#video",
     "videoId": "BCnhtjty2gyQ"
    }
   }
   }
  }
 ]
}

由于items有两个元素，但我想计算snippet中存在的元素数量，我如何计算，我已经解析了json并尝试获取长度，

dynamic result = JsonConvert.DeserializeObject("jsonStr");
foreach (var res in result.items)
{
    int size = res.snippet.count; // Not working
}

Answer 1

(res.snippet as JObject).Count

Answer 2

aspark解决方案的语法略有不同，

private static void Main(string[] args)
{
    string json = @"
        {
            a: 1,
            b: 2,
            c: [
                {c1: 'asdas', c2:231},
                {c1: 'aaaaaa', c2: 100},
                {c1: 'x', c2: 83823}
            ]
        }
        ";

    Console.WriteLine(JObject.Parse(json)["c"].Count());
    //following also works
    Console.WriteLine(o.Property("c").Value.Count());

    //both print 3
}

如何计算C＃中元素的JSON元素数

2 个答案: