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Extract first set of records in JSON C#

I have a requirement to get the first set of records in c# JSON. Here is my JSON data for example
string sJSON = "{
{
"ID": "1",
"Name":"John",
"Area": "Java" ,
"ID": "2",
"Name": "Matt",
"Area": "Oracle" ,
"ID": "3","Name":
"Danny","Area": "Android"
}
}"
I need to extract only the 1st set of records (i.e. {{"ID": "1", "Name":"John", "Area": "Java"}}).
If there is only one record my code (see below) works fine but when there are multiple records it takes the last set of JSON data (i.e. {{"ID": "3","Name": "Danny","Area": "Android"}}).
JObject jsonObject = JObject.Parse(sJSON);
string sID = (string)jsonObject["ID"];
string sName = (string)jsonObject["Name"];
string sArea = (string)jsonObject["Area"];
Can anyone help me extract only the 1st set of JSON data?

You return the JSON data as JSON Array, now it is a simple JSON string.
If you're able to generate like below then you can easily get the single JSON element easily.
[{ "ID": "1", "Name":"John", "Area": "Java" },{ "ID": "2","Name": "Matt","Area": "Oracle" },{ "ID": "3","Name": "Danny","Area": "Android" } ]
Use the below link, to understand this JSON format.
http://json.parser.online.fr/

Parse the data as JToken.
Such that you have something like:
var jToken = JToken.Parse(sJSON);
var isEnumerable = jToken.IsEnumerable()
if(isEnumeable)
{
cast as JArray and get firstOrdefault
}
var isObject = jToken.IsObject();
if(isObject )
{
cast as JObject and perform straight casting
}

JSON.net - Write into JSON / JObject using path string

I have a little utility where we extract values from JSON using JObject.SelectToken(path). We need to determine the paths at run-time. Works perfectly.
What I now need to do is to write back into the JSON (JObject or other) using the same path string. I've hunted and searched and I can't quite find if there is anything that does this quite as cleanly as SelectToken does for reading.
(I'm also stuck in 3.5 CF)
For example, something like:
... JObject read in already ...
var theJToken = theJObject.SelectToken("animals.cat[3].name");
theTJoken.SetValue("Bob"); // Of course this doesn't exist
... serialize it ...

JToken.SelectToken actually returns a JToken which can be modified using JToken.Replace. You can use that to replace the node within your JSON object, mutating the original object.
JObject o = JObject.Parse(#"{ 'cats': [
{ 'name': 'cat 1' },
{ 'name': 'cat 2' },
{ 'name': 'cat 3' } ] }");
// get the token
JToken secondCatName = o.SelectToken("cats[1].name");
// replace the name
secondCatName.Replace("meow");
// and the original object has changed
Console.WriteLine(o.ToString());
// { "cats": [ { "name": "cat 1" }, { "name": "meow" }, { "name": "cat 3" } ] }

Json.NET SelectTokens not working if json contains empty array

I have a valid JSON object that contains multiple "en-US" keys, which I'm trying select. For that purpose I use the JsonPath
"$..en-US"
which is given to the SelectTokens procedure implemented by the Json.NET. It's a JSON framework for .NET . Everything is working fine and well as long as my JSON doesn't contain any empty array.
Here's an example:
var myJsonPath = "$..en-US";
var myJson =
#"{
'controls': [
{
'messages': {
'addSuggestion': {
'en-US': 'Add'
}
}
},
{
'header': {
'controls': []
},
'controls': [
{
'controls': [
{
'defaultCaption': {
'en-US': 'Sort by'
},
'sortOptions': [
{
'label': {
'en-US': 'Name'
}
}
]
}
]
}
]
}
]
}";
var jToken = JObject.Parse(myJson);
var tokens = jToken.SelectTokens(myJsonPath);
Here, the tokens variable will contain just one element! That will be the "en-US" occurence BEFORE the empty array in the 'controls' of the 'header' object. However, when I just leave this 'header' object out:
var myJson =
#"{
'controls': [
{
'messages': {
'addSuggestion': {
'en-US': 'Add'
}
}
},
{
'controls': [
{
'controls': [
{
'defaultCaption': {
'en-US': 'Sort by'
},
'sortOptions': [
{
'label': {
'en-US': 'Name'
}
}
]
}
]
}
]
}
]
}";
I will get all the 3 occurencies of the "en-US" as expected. Btw, if I validate my JsonPath on the first JSON object (i.e. which contains an empty array) in an online tool, then as expected, I get all the three "en-US" cases. This diverges from what I'm getting from the Json.NET. I'm wondering whether it's a bug or do I have to handle this case manually somehow?

This is a bug that has been fixed. Upgrade to the latest version of Json.NET.

If you're in the same situation as me where you're a bit stuck with respect to updating your version of Json.NET, you can work around the issue by doing something along the lines of this:
IEnumerable<JValue> vals = jToken
.Desecendants()
.Where(w => w is JProperty && w.Name=="en-US")
.Select(s => s.Value);
Hope that helps! The vals array will contain the same tokens you would have gotten using the selector you were trying to use before.

Json to C# object with google spreadsheet

EDITED:
If I load a google spreadsheet using JSON URL into a dynamic C# object, I can't access some entries because the JSON looks like this:
"author": [
{
"name": {
"$t": "XYZ"
},
"email": {
"$t": "XYZ#gmail.com"
}
}
]
Why does the google JSON have $ namespaces? Can we remove them? What can be done?
Here is the code:
var json = new WebClient().DownloadString(#"GoogleUrlWithJson");
dynamic jsonObj = JsonConvert.DeserializeObject(json);
string a = jsonObj.feed.entry[0].author.name.$t; ==> Can't compile error "unexpected $"

Try using square bracket syntax to access the JSON property names that have $ in them:
string a = jsonObj.feed.entry[0].author.name["$t"];

Can I LINQ a JSON?

This is the JSON I get from a request on .NET:
{
"id": "110355660738",
"picture": {
"data": {
"url": "https://fbcdn-profile-a.akamaihd.net/hprofile-ak-prn2/1027085_12033235063_5234302342947_n.jpg",
"is_silhouette": false
}
}
}
and I'd like to catch the field "url", using (maybe?) LINQ. I do many request as this, that differents a bit. So I won't to create a C# Class and deserialize it every time.
Is it a way to extract a single field? Thank you!

No need for Linq, just use dynamic (using Json.Net)
dynamic obj = JObject.Parse(json);
Console.WriteLine((string)obj.picture.data.url);
Linq version would not be much readable
JObject jObj = JObject.Parse(json);
var url = (string)jObj.Descendants()
.OfType<JProperty>()
.Where(p => p.Name == "url")
.First()
.Value;
Documentation: LINQ to JSON

I would not recommend LINQ. I would recommend a JSON library such as newtonsoft.json.
So you can do this:
string json = #"{
""Name"": ""Apple"",
""Expiry"": "2008-12-28T00:00:00",
""Price"": 3.99,
""Sizes"": [
""Small"",
""Medium"",
""Large""
]
}";
JObject o = JObject.Parse(json);
string name = (string)o["Name"];
// Apple
JArray sizes = (JArray)o["Sizes"];
string smallest = (string)sizes[0];
// Small
Note:- this code has been copied from the samples present on the project site
http://james.newtonking.com/pages/json-net.aspx

In a bind you could always deserialize the JSON and serialize it to XML, and load the XML in a XDocument. Then you can use the classic Linq to XML. When you are done take the XML, deserialize it, and serialize it back to JSON to JSON. We used this technique to add JSON support to an application that was originally built for XML, it allowed near-zero modifications to get up and running.

You can easily query with LINQ like this
considering this JSON
{
"items": [
{
"id": "10",
"name": "one"
},
{
"id": "12",
"name": "two"
}
]
}
let's put it in a variable called json like this,
JObject json = JObject.Parse("{'items':[{'id':'10','name':'one'},{'id':'12','name':'two'}]}");
you can select all ids from the items where name is "one" using the following LINQ query
var Ids =
from item in json["items"]
where (string)item["name"] == "one"
select item["id"];
Then, you will have the result in an IEnumerable list