Parsing JSON with JSON.NET

Question

I have a JSON string:

 {"responseData": 
     {"results": [
         {"GsearchResultClass": "GblogSearch",
          "title":"\u003cb\u003eParis Hilton\u003c/b\u003e shops at Sydney Michelle boutique in the Beverly Glen \u003cb\u003e...\u003c/b\u003e",
           "titleNoFormatting":"Paris Hilton shops at Sydney Michelle boutique in the Beverly Glen ...",
           "postUrl":"http://www.celebrity-gossip.net/celebrities/hollywood/paris-hilton-sydney-michelle-stockup-215844/",
           "content":"\u003cb\u003eParis Hilton\u003c/b\u003e shops at Sydney Michelle boutique in the Beverly Glen Mall - \u003cb\u003eParis Hilton\u003c/b\u003e: Sydney Michelle Stockup.",
           "author":"The Gossip Girls at (c) gossipgirls.com",
           "blogUrl":"http://www.celebrity-gossip.net/",
           "publishedDate":"Tue, 23 Feb 2010 22:26:00 -0800"
         },
         {"GsearchResultClass":"GblogSearch",
          "title":"\u003cb\u003eParis Hilton\u003c/b\u003e having wardrobe woes as she met with her lawyer",
          "titleNoFormatting":"Paris Hilton having wardrobe woes as she met with her lawyer",
          "postUrl":"http://www.celebrity-gossip.net/celebrities/hollywood/paris-hiltons-wardrobe-woes-215855/",
          "content":"\u003cb\u003eParis Hilton\u003c/b\u003e having wardrobe woes as  she met with her lawyer - \u003cb\u003eParis Hilton's\u003c/b\u003e Wardrobe Woes.",
          "author":"The Gossip Girls at (c) gossipgirls.com","blogUrl":"http://www.celebrity-gossip.net/",
          "publishedDate":"Wed, 24 Feb 2010 11:07:56 -0800"
         },
         {"GsearchResultClass":"GblogSearch",
          "title":"HOT GALLERY: \u003cb\u003eParis Hilton\u003c/b\u003e Turns Her Frown Upside Down | OK \u003cb\u003e...\u003c/b\u003e",
          "titleNoFormatting":"HOT GALLERY: Paris Hilton Turns Her Frown Upside Down | OK ...",
          "postUrl":"http://www.okmagazine.com/2010/02/hot-gallery-paris-hilton-turns-her-frown-upside-down/",
          "content":"\u003cb\u003eParis Hilton\u003c/b\u003e kept her game face on yesterday as she headed to a meeting in Hollywood. The socialite maintained her composure, but eventually cracked a smile, 201002.",
          "author":"Brittany Talarico",
          "blogUrl":"http://www.okmagazine.com/",
          "publishedDate":"Wed, 24 Feb 2010 07:57:10 -0800"
         },
         {"GsearchResultClass":"GblogSearch",
          "title":"Love It Or Hate It: \u003cb\u003eParis Hilton\u003c/b\u003e | ImNotObsessed.com",
          "titleNoFormatting":"Love It Or Hate It: Paris Hilton | ImNotObsessed.com",
          "postUrl":"http://www.imnotobsessed.com/2010/02/24/love-it-or-hate-it-paris-hilton",
          "content":"tweetmeme_url \u003d \"http://www.imnotobsessed.com/2010/02/24/love-it-or-hate-it-\u003cb\u003eparis\u003c/b\u003e-\u003cb\u003ehilton\u003c/b\u003e\";tweetmeme_element_id \u003d '#tweetmeme-widget-139430e62dc37d7a2aa71840d6444572';That's some dress \u003cb\u003eParis Hilton\u003c/b\u003e was seen wearing while shopping in ...",
          "author":"Vera",
          "blogUrl":"http://www.imnotobsessed.com/",
          "publishedDate":"Wed, 24 Feb 2010 10:44:28 -0800"
         }],
    "cursor": { 
        "pages": [
            {"start":"0","label":1},
            {"start":"4","label":2},
            {"start":"8","label":3},
            {"start":"12","label":4},
            {"start":"16","label":5},
            {"start":"20","label":6},
            {"start":"24","label":7},
            {"start":"28","label":8}],
        "estimatedResultCount":"8035445",
        "currentPageIndex":0,
        "moreResultsUrl":"http://blogsearch.google.com/blogsearch?oe\u003dutf8\u0026ie\u003dutf8\u0026safe\u003dactive\u0026source\u003duds\u0026start\u003d0\u0026hl\u003den\u0026q\u003dParis+Hilton"
        }
     }, 
"responseDetails": null, 
"responseStatus": 200}

ed. note: line breaks added for readability

and I'm using Json.NET to parse it, however its giving me a null

this is my code:

JObject o = JObject.Parse(json); // <- where json is the string above

string name = (string)o["responseData"];

BUT its giving me this error :

Can not convert {null} to String.

Answer 1

Have you tried things like?

string gsearchresultclass= (string)o["responseData"]["results"][0]["GsearchResultClass"];
string title= (string)o["responseData"]["results"][0]["title"];
string titlenoformat= (string)o["responseData"]["results"][0]["titleNoFormatting"];
string url = (string)o["responseData"]["results"][0]["postUrl"];
string content = (string)o["responseData"]["results"][0]["content"];
string author = (string)o["responseData"]["results"][0]["author"];
string blogurl = (string)o["responseData"]["results"][0]["blogUrl"];
string date = (string)o["responseData"]["results"][0]["publishedDate"];

What exactly are you trying to get into the name variable?

Answer 2

http://msdn.microsoft.com/en-us/library/system.runtime.serialization.json.datacontractjsonserializer.aspx
Its a good alternative to your method, that I would recommend...
Hope that helps...

Answer 3

If you're posting your JSON object raw to the Web API then you will run into this problem. The Deserializer is expecting an actual string and not an object or an array. Because it is using a JsonMediaTypeFormatter, it won't know how to translate what is being passed to it.

You need to do the following to avoid the null:

public HttpResponseMessage postBlogSearch([FromBody] JToken json){
    var jsonResult = JObject.Parse(json.ToString());
    var name = jsonResult["responseData"].ToString();
}

For more information see this article.

Answer 4

Using Json.Net, you can deserialize the object like this:

BlogSearch search = JsonConvert.DeserializeObject<BlogSearch>(content);

You would define the BlogSearch object like this:

[JsonObject(MemberSerialization.OptIn)]
public class BlogSearch
{
    [JsonProperty(PropertyName = "responseData")]
    public BlogSearchResponse SearchResponse { get; set; }
}

You keep defining objects until you have all the ones you are interested in.