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writing json string to firestore in c#

I have a json string:
var jsonstr = "{ 'property1: 'myvalue','property2':2 }";
JObject json2 = JObject.Parse(jsonstr);
and want to write to firestore but the values are empty arrays instead of the values.
var task = collection.Document("test2").SetAsync(json2);

NewtonSoft JSON : https://www.newtonsoft.com/json
You're going to want to Serialize your object.
var settings = new JsonSerializerSettings { TypeNameHandling = TypeNameHandling.All };
var text = JsonConvert.SerializeObject(configuration, settings);

The json is missing a closing ' character on property1. Technically, you should be using double quotes instead of single on JSON.
var jsonstr = "{ 'property1': 'myvalue','property2':2 }";

Add a Root Key for an Orphan JSON using C#

I need to add a Key for the Orphan JSON object
JSON String:
string jsonString = "{\"FirstName\":\"Emma\",\"LastName\":\"Watson\"}";
Expected JSON String:
string jsonString = "{\"PersonName\":{\"FirstName\":\"Emma\",\"LastName\":\"Watson\"}}";
I need to add a Key for the above said actual JSON string as like expected JSON using C#.
I tried the following code:
string rootKey = "PersonName";
string jsonString = "{\"FirstName\":\"Emma\",\"LastName\":\"Watson\"}";
var jObj = JObject.Parse(jsonString);
// Need to add a ROOT Key for this jObj...
Simillar to the existing question How to add a key to a JSON array value?

You're not adding a property to the object, you're putting the object in another object. Just think of it as a dictionary. Create a "dictionary" and add your object to it. Then you could get the json string back from that object.
var jsonString = "{\"FirstName\":\"Emma\",\"LastName\":\"Watson\"}";
var jsonObj = JObject.Parse(jsonString);
var newObj = new JObject
{
["PersonName"] = jsonObj,
};
var newJsonString = newObj.ToString();

Deserializing JSON response without creating a class

From the result of an API call I have a large amount of JSON to process.
I currently have this
Object convertObj = JsonConvert.DeserializeObject(responseFromServer);
I am aware that I could do something like
Movie m = JsonConvert.DeserializeObject<Movie>(responseFromServer);
And then use it like
m.FieldName
m.AnotherField
//etc
Ideally I would like to do something like
var itemName = convertObj["Name"];
to get the first Name value for the first item in the list.
Is this possible, or do I have to create a class to deserialize to?
The reason I do not want to create the class is I am not the owner of the API and the field structure may change.
Edit.
Okay so I created the class as it seems the best approach, but is there a way to deserialize the JSON into a list?
var sessionScans = new List<SessionScan>();
sessionScans = JsonConvert.DeserializeObject<SessionScan>(responseFromServer);
Complains that it cannot convert SessionScan to generic list.

No need to use dynamic, you can simply use JToken which is already does what you expect:
var json = #"
{
""someObj"": 5
}
";
var result = JsonConvert.DeserializeObject<JToken>(json);
var t = result["someObj"]; //contains 5

With .NET 6, this can be done as below,
using System.Text.Json;
using System.Text.Json.Nodes;
string jsonString = #"some json string here";
JsonNode forecastNode = JsonNode.Parse(jsonString)!;
int temperatureInt = (int)forecastNode!["Temperature"]!;
Console.WriteLine($"Value={temperatureInt}");
//for nested elements, you can access as below
int someVal = someNode!["someParent"]["childId"]!.ToString();
Refer this MS docs page for more samples - create object using initializers, make changes to DOM, deserialize subsection of a JSON payload.

You can try with JObject.Parse :
dynamic convertObj = JObject.Parse("{ 'Name': 'Jon Smith', 'Address': { 'City': 'New York', 'State': 'NY' }, 'Age': 42 }");
string name = convertObj.Name;
string address = convertObj.Address.City;

The below example can deserialize JSON to a list of anonymous objects using NewtonSoft.Json's DeserializeAnonymousType method.
var json = System.IO.File.ReadAllText(#"C:\TestJSONFiles\yourJSONFile.json");
var fooDefinition = new { FieldName = "", AnotherField = 0 }; // type with fields of string, int
var fooListDefinition = new []{ fooDefinition }.ToList();
var foos = JsonConvert.DeserializeAnonymousType(json, fooListDefinition);

You can use Json.NET's LINQ to JSON API
JObject o = JObject.Parse(jsonString);
string prop = (string)o["prop"];

Use Newtonsoft.Json
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
var json = "[{'a':'aaa','b':'bbb','c':'ccc'},{'a':'aa','b':'bb','c':'cc'}]";
var ja = (JArray)JsonConvert.DeserializeObject(json);
var jo = (JObject) ja[0];
Console.WriteLine(jo["a"]);

I had this problem working with unknown APIs then I decide to come over this problem using this approach, I'm writing down here my test case:
[TestMethod]
public void JsonDocumentDeserialize()
{
string jsonResult = #"{
""status"": ""INTERNAL_SERVER_ERROR"",
""timestamp"": ""09-09-2019 11:00:24"",
""message"": ""documentUri is required.""
}";
var jDoc = JsonDocument.Parse(jsonResult);
if (jDoc.RootElement.TryGetProperty("message", out JsonElement message))
{
Assert.IsTrue(message.GetString() == "documentUri is required.");
}
}
it worked for me because first I was looking to find a way to use dynamic type as it's mentioned in Azure Function HTTPTrigger. But I found this approach most useful and robust.
Microsoft Reference

C# deserialization

How to deserialize with keyvaluepair the above json
string stations = [{"2":false,"1":"Aforre","0":"WS6"},{"2":false,"1":"Alodtau","0":"WS3"},{"2":false,"1":"Balimo Station","0":"WS36"}]
I what like this
var get = js.Deserialize<Dictionary<string,dynamic>>(stations);

try this:
string stations = "[{'2':false,'1':'Aforre','0':'WS6'},{'2':false,'1':'Alodtau','0':'WS3'},{'2':false,'1':'Balimo Station','0':'WS36'}]";
var serializer = new JavaScriptSerializer();
dynamic value = serializer.DeserializeObject(stations);
and you can access objects like:
var a = value[0]["0"];
and a will have "WS6" (according to your JSON)

The JSON shown is an array. You might try desetializing to:
Dictionary<string, object>[]
i.e.
var get = js.Deserialize<Dictionary<string,object>[]>(stations);

One of the best option is create a class that consist of all keyvalue pair and then deserialize json string to the object of created class

You can try using dynamic variable as following:
string stations = "[{'2':false,'1':'Aforre','0':'WS6'},{'2':false,'1':'Alodtau','0':'WS3'},{'2':false,'1':'Balimo Station','0':'WS36'}]";
var serializer = new JavaScriptSerializer();
dynamic serializevalues = serializer.DeserializeObject(stations);
var valueof1 = serializevalues[0]["1"];
Response.Write(valueof1);
The above will print output "Aforre'.

Library to Create a JSONObject in .NET Framework

I am looking for a JSON library which is able to do the following:
PC 1
JSONObject obj = new JSONObject();
obj.put("name", "mkyong.com");
obj.put("age", new Integer(100));
PC 2
JSONObject jsonObject = (JSONObject) obj;
String name = (String) jsonObject.get("name");
System.out.println(name);
long age = (Long) jsonObject.get("age");
System.out.println(age);
As you can see, there was no need to create a class in order to send the name and age value pairs. Now, this code is in Java. Is there a library in .NET which does this? I checked the documentation for JSON.NET, however it appears that it does not offer the use of a JSONobject where we can add value pairs.

You can use Json.Net
dynamic jsonObject = new JObject();
jsonObject.Name = "mkyong.com";
jsonObject.Age = 100;
var json = jsonObject.ToString();
output:
{
"Name": "mkyong.com",
"Age": 100
}
or without dynamic
JObject jsonObject = new JObject();
jsonObject["Name"] = "mkyong.com";
jsonObject["Age"] = 100;
var json = jsonObject.ToString();
You can even make use of anonymous classes
var json = JsonConvert.SerializeObject(new {Name="mkyong.com", Age=100 });