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C# find JSON value based only on Key name through multiple levels of array

I have a variety of input JSON formatted data which all contain a particular key-name terminalSize. This is the only piece I know. The total number of JSON trees or the exact depth of terminalSize inside the JSON tree will forever be an unknown and subject to change.
I'm looking for a C# solution to loop through every child of the JSON string and find terminalSize then fetch the value.
I've tried this with success but it will only work if terminalSize is in the first level of the JSON:
var list = JsonConvert.DeserializeObject<List<Dictionary<string, string>>>(jsonString);
var dict = list.SelectMany(d => d).ToDictionary(p => p.Key, p => p.Value);
var terminal = dict["terminalSize"];
Example 1.
{
"status": "success",
"data": {
"terminalSize": 3766505.46,
"totalTerminalSize": 3766505.46
},
"message": null
}
Example 2.
{
"lastUpdated": 1588020678,
"terminalData": {
"terminalSize": "451679852",
"totalTerminalSize": "2100000000"
},
"terminalValueSeries": {
"8x7": 2.33,
"8x6": 3.73,
"8x5": 4.49,
"8x4": 3.68,
"8x3": 13998,
"8x2": 274936,
"8x1": 5.09
}
}
Example 3.
{
"terminalSize": "492612346.17",
"terminalStatus": "online"
}

You can parse your JSON to a JToken, then use SelectToken with the recursive descent JsonPath operator .. to get the terminalSize anywhere in the JSON:
var terminalSize = (double?) JToken.Parse(json).SelectToken("$..terminalSize");
Fiddle: https://dotnetfiddle.net/5ziYbP
If there might be multiple terminalSize keys in the JSON, for example if you had an array of terminals, you can use SelectTokens instead and put the terminal sizes into a Dictionary keyed by path:
var sizes = JToken.Parse(json4)
.SelectTokens("$..terminalSize")
.ToDictionary(t => t.Path, t => (double)t);
Fiddle: https://dotnetfiddle.net/ivSM88

You could also use linq and filter the JProperty collection based on JProperty.Name. For example
var result = JObject.Parse(jsonString)
.DescendantsAndSelf()
.OfType<JProperty>()
.Single(x=>x.Name.Equals("terminalSize"))
.Value;

You may parse your JSON into JObject, then recursively go through all properties and sub objects to find a terminalSize value. There is no need to deserialize the entire JSON into specific object
var json = JObject.Parse(jsonString);
var result = GetTerminalSize(json);
double GetTerminalSize(JObject input)
{
foreach (var property in input.Properties())
{
if (property.Name == "terminalSize")
return property.Value.Value<double>();
if (property.Value.Type == JTokenType.Object)
return GetTerminalSize((JObject) property.Value);
//not sure, if the is a need to handle an array
if (property.Value.Type == JTokenType.Array)
foreach (var item in (JArray) property.Value)
return GetTerminalSize((JObject) item);
}
return 0;
}
It returns a correct value for all 3 examples

selecting the first 2 FIELDS in a JSON OBJECT

I have some JSON that looks like this:
{
"innerObj1": {
"1. Information": "unimportant"
},
"innerObj2": {
"2017-09-19 16:00:00": {
"number1": "75.4500"
},
"2017-09-19 15:55:00": {
"number2": "75.4200"
}
}
}
Not sure why innerObj2 is not returned as an array (this is from an api) but I have to get number1 and number2 returned as an array of strings. Note that 2017-09-19 16:00:00 and 2017-09-19 15:55:00 are subject to change, so I can't hardcode the selection of those objects in C#. I was thinking of possibly using LINQ, but I'm not sure how. I've really only used them with JSON arrays.

Assuming you are using Json.Net, you can get the values of the innermost properties into an array like this, without needing to know the names of them:
JObject obj = JObject.Parse(json);
string[] numbers = ((JObject)obj["innerObj2"]).Properties()
.SelectMany(jp => ((JObject)jp.Value).Properties())
.Select(jp => (string)jp.Value)
.ToArray();
Fiddle: https://dotnetfiddle.net/5sLy6M
Or, a simpler alternative which does the same thing using SelectTokens with a JSONPath wildcard expression:
string[] numbers = obj.SelectTokens("innerObj2.*.*")
.Select(jt => (string)jt)
.ToArray();
Fiddle: https://dotnetfiddle.net/CyRQ9T

ASP.NET getting indexed values when deserializing JSON into a dynamic object

So I have a JSON string that I am passing from an AJAX call to my controller. I have a list of indexed values that I am passing into a dynamic object.
I deserialize the JSON with
JsonConvert.DeserializeObject<dynamic>(s)
This is the output from that dynamic object:
"RolePermissions[0].RolePermissionId": "269",
"RolePermissions[0].HasAccess": "false",
"RolePermissions[1].RolePermissionId": "270",
"RolePermissions[1].HasAccess": "false",
"RolePermissions[2].RolePermissionId": "271",
"RolePermissions[2].HasAccess": "true",
"RolePermissions[3].RolePermissionId": "272",
"RolePermissions[3].HasAccess": "false"
When I try to access the a property of the object with
ssObj.RolePermissions[0].RolePermissionId
I get a RuntimeBinderException. I have tried to use JObject.Parse, which works great, but for some reason, the values in the array become out of order.
Any help would be greatly appreciated. Thanks!

When you try to do RolePermissions[0].RolePermissionId you are trying to access a nested collection containing an object with a property RolePermissionId at index 0. But your JSON doesn't represent a hierarchy of objects, it represents a single flat object with key/value pairs whose keys contain periods and brackets. Since c# identifiers don't allow such characters so you have no way to access such property values using dynamic directly.
Instead, your options include:
Take advantage of the fact that JsonConvert.DeserializeObject<dynamic>(s) actually returns a JObject and use its dictionary indexer:
var ssObj = JsonConvert.DeserializeObject<dynamic>(s);
var rolePermissionId = (string)ssObj["RolePermissions[0].RolePermissionId"];
If you prefer a slightly more typed solution, you could deserialize to a Dictionary<string, dynamic>:
var ssDict = JsonConvert.DeserializeObject<Dictionary<string, dynamic>>(s);
var rolePermissionId = (string)ssDict["RolePermissions[0].RolePermissionId"];
Or for a much more statically typed solution, parse explicitly to a JObject and use LINQ to JSON:
var jObj = JObject.Parse(s);
var rolePermissionId = (string)jObj["RolePermissions[0].RolePermissionId"];
Sample fiddle showing the various options.

If you are in control of the data being sent via AJAX then make sure the data sent is properly formatted.
In order to be able to deserialize variable s like:
var ssObj = JsonConvert.DeserializeObject<dynamic>(s);
and access the resulting object in this manner:
ssObj.RolePermissions[0].RolePermissionId
then the JSON value in s, based on your sample and desired behavior, would have to look like this:
{
"RolePermissions": [
{
"RolePermissionId": "269",
"HasAccess": "false"
},
{
"RolePermissionId": "270",
"HasAccess": "false"
},
{
"RolePermissionId": "271",
"HasAccess": "true"
},
{
"RolePermissionId": "272",
"HasAccess": "false"
}
]
}
This quick unit test showed that it is possible to get indexed values when deserializing JSON into a dynamic object
[TestClass]
public class UnitTest1 {
[TestMethod]
public void GetIndexedValuesWhenDeserializingJSONIntoDynamicObject() {
var s = #"
{
'RolePermissions': [
{
'RolePermissionId': '269',
'HasAccess': 'false'
},
{
'RolePermissionId': '270',
'HasAccess': 'false'
},
{
'RolePermissionId': '271',
'HasAccess': 'true'
},
{
'RolePermissionId': '272',
'HasAccess': 'false'
}
]
}
";
var ssObj = JsonConvert.DeserializeObject<dynamic>(s);
var result = ssObj.RolePermissions[0].RolePermissionId;
Assert.AreEqual("269", (string)result);
}
}
So you need to make sure you are sending well formatted JSON to your controller to achieve desired behavior.

Condense into an object with JSON.net

I'm working with an API with an example output of the following
{
"id": 12345678
"photo-url-1280": "http://68.media.tumblr.com/5076e813bdc463409f59172b2c152487/tumblr_ocy8peMYvo1uur5s9o1_1280.png",
"photo-url-500": "http://67.media.tumblr.com/5076e813bdc463409f59172b2c152487/tumblr_ocy8peMYvo1uur5s9o1_500.png",
"photo-url-400": "http://68.media.tumblr.com/5076e813bdc463409f59172b2c152487/tumblr_ocy8peMYvo1uur5s9o1_400.png",
"photo-url-250": "http://67.media.tumblr.com/5076e813bdc463409f59172b2c152487/tumblr_ocy8peMYvo1uur5s9o1_250.png",
"photo-url-100": "http://67.media.tumblr.com/5076e813bdc463409f59172b2c152487/tumblr_ocy8peMYvo1uur5s9o1_100.png",
"photo-url-75": "http://67.media.tumblr.com/5076e813bdc463409f59172b2c152487/tumblr_ocy8peMYvo1uur5s9o1_75sq.png",
}
Those last items are very related, so I'd like to move them into their own object.
As of now, getting a specified image would be super messy. Getting the 400px version might look like this -
myPhotoObject.Photo400
However, if I was able to move these URLs into an object of their own, I could more cleanly call it like the following:
myPhotoObject.Photo.400
or even introduce more friendly methods
myPhoto.Photo.GetClosestTo(451);
There is a pattern in the URLs here - after an _ character, the identifying size is shown e.g. ..._1280.png and ..._500.png
Would the best way to get these be to write a getter property that just appends a list of known sizes to a URL? Would this way be any less/more efficient than using purely the JSON.net converters?

I suggest to parse your JSON into a dictionary first, as described here, and then manually copy it to a more structured object:
Dictionary<string, string> dict = JsonConvert.DeserializeObject<Dictionary<string, string>>(json);
var myImageObject = new { Id = "", Images = new Dictionary<int, string>()};
foreach(var key in dict.Keys) {
if(key == "id") {
myImageObject.Id = dict[key]
}
else {
var imageSize = ParseForImageSize(key);
myImageObject.Images.Add(imageSize, dict[key])
}
}

MongoDB Get names of all keys in collection using c#

How can I get names of all the keys in a MongoDB collection using c#.
I am using mongocsharpdriver.
I am able to get all the records using
var collection1 = database1.GetCollection("Games").FindAll();
Now I need the key names to display/use it. I need key names of collection that I have fetched.
e.g. If I have collection which
{ "_id" : ObjectId("c3"), "GameID" : 20, "GameName" : "COD5", "Cost" : 100}
{ "_id" : ObjectId("c4"), "GameID" : 21, "GameName" : "NFS", "Publisher" : "EA"}
{ "_id" : ObjectId("c5"), "GameID" : 22, "GameName" : "CS", "Cost" : 200}
So I should get list of keys like GameID, GameName, Cost, Publisher.
I also went through MongoDB Get names of all keys in collection but was not able to implement it, didnot understood it & got problem with mapreduce.

Inspired from the link in your question:
string map = #"function() {
for (var key in this) { emit(key, null); }
}";
string reduce = #"function(key, stuff) { return null; }";
string finalize = #"function(key, value){
return key;
}";
MapReduceArgs args = new MapReduceArgs();
args.FinalizeFunction = new BsonJavaScript(finalize);
args.MapFunction = new BsonJavaScript(map);
args.ReduceFunction = new BsonJavaScript(reduce);
var results = collection1.MapReduce(args);
foreach (BsonValue result in results.GetResults().Select(item => item["_id"]))
{
Console.WriteLine(result.AsString);
}

A very inefficient, but simple way to do this is
HashSet<string> keys = new HashSet<string>();
foreach (var rover in collection1.FindAll())
{
rover.Names.ToList().ForEach(p => keys.Add(p));
}
Keep in mind that finding the set of keys, no matter how it's implemented, will always have to iterate the entire collection, so it will be terribly slow on larger collections.
It makes sense to use Map/Reduce for this problem on larger collections, because that avoids all the data transfer and deserialization overhead that is incurred by the solution I posted above, but you should generally try to avoid doing something like this at all. At least, don't do it where it's needed synchronously.
If you somehow need to know the set of all fields quickly, you're better off keeping track of the fields during writes and store the list of fields in a separate collection somewhere.