Json.net parsing

[cengineer]

I am accessing the facebook api and using the json.net library (newtonsoft.json.net) I declare a Jobject to parse the content and look for the specific elements and get their values. Everything works fine for the first few but then I get this unexplained nullexception error " (Object reference not set to an instance of an object)

Now I took a look at the declaration but cannot see how to change it. Any help appreciated:

Dim jobj as JObject = JObject.Parse(responseData)
message = jobj("message").tostring

The error occurs at the last line above.I check to see if message is null and then look for the next desired field as follows

catch exception..
  dim jobj2 as JObject = JObject.parse(responseData)
  description = jobj2("description").tostring

JSON responsedata:

{
   "id": "5281959998_126883980715630",
   "from": {
   "name": "The New York Times",
   "category": "Company",
   "id": "5281959998"
},
  "picture": "http://external.ak.fbcdn.net  /safe_image.php?d=e207958ca7563bff0cdccf9631dfe488&w=
90&h=90&url=http\u00253A\u00252F\u00252Fgraphics8.nytimes.com\u00252Fimages\u00252F2011\u00252F02\u00252F04\u00252Fbusiness\u00252FMadoff\u00252FMadoff-thumbStandard.jpg",
  "link": "http://nyti.ms/hirbn0",
   "name": "JPMorgan Said to Have Doubted Madoff Long Before His Scheme Was Revealed",
   "caption": "nyti.ms",
   "description": "Newly unsealed court documents show that bank
   executives were suspicious of Bernard Madoff\u2019s accounts 
   and steered clients   away from him but did not alert regulators.",
   "icon": "http://static.ak.fbcdn.net/rsrc.php/yD/r/aS8ecmYRys0.gif",
   "type": "link",
   "created_time": "2011-02-04T16:09:03+0000",
   "updated_time": "2011-02-06T20:09:51+0000",
  "likes": {
  "data": [
     {
        "name": "Siege Ind.",
        "category": "Product/service",
        "id": "152646224787462"
     },
     {
        "name": "Lindsey Souter",
        "id": "100000466998283"
     },

This is one example where "message" does not appear in the first few lines but appears later. So what I do is look for position of message and description and which ever is first go and get that and if I get an error or the fields do not return anything, I try and parse by regex and even that is not working right.

[dolot]

I couldn't possibly tell you what's going on json wise - perhaps newtonsoft has a forum of their own for these questions? I work with a third party package made by esri, and they have their own forum for asking and answering questions specific to their product.

But as for your code, rather than doing a Try...Catch, perhaps you could do something like this:

Dim jobj as JObject = JObject.Parse(responseData)
if jobj isnot nothing then
    'do something
else
    'do something else
end if

[cengineer]

Thank you for your response.