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Need help deserializing C# / .NET 6 into seperate objects

I am attempting to use JsonSerializer.Deserialize() from System.Text.JSON in .NET 6.
I have no control over the format of the JSON.
I have used it successfully in the past but now the data I need to consume is more complicated (but not VERY complicated). I am assuming that I am simply describing my data incorrectly.
I have tried several things.... but the description below is the only way so far that I could consume the data at all.
I think my biggest problem is that I am trying to use the wiz-bang "Paste Special -> Paste JSON as Classes" without really understanding how to form my classes for serialization/deserialization.
Here is a simple example of the JSON I am trying to consume:
[
{
"version": "1.0b",
"sub_version": "x.y.barf"
},
{
"somestring": "I am a string",
"isCool": false,
"a_cool_array": [
"bob",
"jill",
"pete"
]
}
]
If I use the whiz-bang "Paste Special" tool, I get the following generated for me.
public class Rootobject
{
public Class1[] Property1 { get; set; }
}
public class Class1
{
public string version { get; set; }//<-- I need these to remain in their own object
public string sub_version { get; set; }//<-- I need these to remain in their own object
public string somestring { get; set; }
public bool isCool { get; set; }
public string[] a_cool_array { get; set; }
}
Here is the problem that I have.
The whiz-bang tool put my first object (with one version strings) and second (more complicated) object into the same object.
If I use a call like this:
var deserializedJSON = JsonSerializer.Deserialize<List<Class1>>(myJSONTextHere);
I end up with two objects in the list.
The first one has the versions filled out, the second one only has the other fields filled out.
This all makes sense to me but I don't know how to get around the problem.
I need these objects to model the JSON and I need them to save back in the same format when I re-serailize the modified classes elsewhere. This isn't my exact problem as I have simplified it for the question.

I have found one way around this problem.
It is ugly but seems to work. I hate that my code has to know about the data it is manipulating.
I used the actual JSON DOM to split the two disparate classes into individual JSON objects, then used the class de-serializer to load the individual objects into their given types.
In the following example, I am not checking anything.. I happen to know the order of the objects. I could check the raw JSON to make sure it was what I was looking for. In this case, I don't need to.
So, instead of taking the class structure as pasted by the super spiffy "Paste Classes from JSON" thingamajigger.. I split the classes myself.
Like this:
public class VersionClass
{
public string version { get; set; }
public string sub_version { get; set; }
}
public class DataClass
{
public string somestring { get; set; }
public bool isCool { get; set; }
public string[] a_cool_array { get; set; }
}
Then, I can load the JSON into the objects I need like this:
using var jsonDoc = JsonDocument.Parse(jsonText);
var versionClass = jsonDoc.RootElement[0].Deserialize<VersionClass>();
var dataClass = jsonDoc.RootElement[1].Deserialize<DataClass>();
I hope this helps someone having the same problem.

Your json needs to look like this:
{
"class1": [
//more json
],
"class2": [
//more json
]
}
Then you will have:
public class RootObject
{
// class1 and 2 in here
}
public class Class1
{
}
public class Class2
{
}

Process XML output from API

I am getting an XML return from an Ebay API call. This is actually an Ebay category list of collections. But the problem is, I can't access its collection from XML output. I have attached two pictures - the first one showing debug of XML value returning variable, and the second one showing "InnerList". My main goal is prepare this XML data to store on my database, so I need a clean list of values from XML data. Any ideas?

You could deserialize your xml into your own class/object - Then it might be easier to work with. All i do is put xml tags to a class and i can deserialize it. See the class and method below:
public static T Deserialize<T>(string xmlText)
{
try
{
var stringReader = new System.IO.StringReader(xmlText);
var serializer = new XmlSerializer(typeof(T));
return (T)serializer.Deserialize(stringReader);
}
catch
{
throw;
}
}
[XmlElement("adress")]
public class Adress
{
[XmlElementAttribute("street_address")]
public string street_address { get; set; }
[XmlElementAttribute("postal_code")]
public string postal_code { get; set; }
[XmlElementAttribute("city")]
public string city { get; set; }
[XmlElementAttribute("country")]
public string country { get; set; }
}
public main()
{
Adress myAdress = Deserialize<Adress>(XMLstring);
}
Hope it helps!

It seems you are using Ebay SDK. Please try code below to process return values.
foreach (CategoryTypeCollection item in categories)
{
item.ItemAt(0).CategoryID = "This is how you access the properties of he returned result";
// THE XML is already parsed for you via SDK, so you don't have to parse it...
// since i wrote foreach loop here, always access itemAt 0th index posiiton
}

Separating array and element from a JSON string

I am connecting you Google Places API to retrive results in the form of a JSON string. You can view the complete format of the string Here.
If you a look at it you will see that the actual results array starts after two elements which are html_attributions and next_page_token.
So When i try to deserialize it in this way:
var serializer = new JavaScriptSerializer();
var arr= serializer.Deserialize(result,typeof(string[]));
I get an empty array.
My question is how is there a way i can separate html_attributions and next_page_token fields and the pass the valid results array from the string to be deserialized?

I don't understand the part where you wish to seperate the html_attributions and the next_page_token.
Wouldn't it be sufficient to just deserialize the response with whatever properties that you need?
For example, you can deserialize the response to only retrieve the values that you desire;
// I represent the wrapper result
class Result
{
public List<string> html_attributions { get; set; }
public string next_page_token { get; set; }
public List<ResultItem> results { get; set; }
}
// I represent a result item
class ResultItem
{
public string id { get; set; }
public string name { get; set; }
}
// the actual deserialization
Result Deserialize(string json)
{
var serializer = new JavaScriptSerializer();
return serializer.Deserialize(json, typeof(Result));
}
Edit:
The reason that your deserialization doesn't return you a array of strings is because the response that you retrieve is infact an object and not an array, however the parameter within that object which is named results is an array. In order for you to deserialize more properties you'll have to define them in your "ResultItem" class, sorry for my poor naming here.
For instance, if you'd wish to also retrieve the icon property per result you'll have to add a property named "icon" of type string.
Meanwhile the property "photos" is an array, in order to deserialize it you'll have to create another class and add a property of type list/array of that newly created class, and it has to be named "photos" unless you use a different serializer or use DataContract and DataMember attributes (using the Name property for field mapping).
// the representation of a photo within a result item
class Photo
{
public int height { get; set; }
public List<string> html_attributions { get; set; }
public string photo_reference { get; set; }
public int width { get; set; }
}
// I represent a result item
class ResultItem
{
public string id { get; set; }
public string name { get; set; }
// the added icon
public string icon { get; set; }
// the added photos collection, could also be an array
public List<Photo> photos { get; set; }
}
Just look at the JSON result to figure out what other properties that you might want to add, for instance the "scope" property is an string whilst the "price_level" is an integer.
If I understand your comment correctly you're only interested in the actual results, you'll still have to deserialize the response correctly with its wrapper.
// the actual deserialization
List<ResultItem> Deserialize(string json)
{
var serializer = new JavaScriptSerializer();
var result = serializer.Deserialize(json, typeof(Result));
return result.results;
}
Edit2:
If you really want a string[] as a result you could simply take use of System.Linq using the code above.
string[] stringArray = result.results.Select(r => string.Format("id:{0} - name:{1}", r.id, r.name)).ToArray();
Edit3:
Instead of using the JavascriptSerializer you could use JObject functionality which can be found in the Newtonsoft.Json.Linq library.
var jsonObject = JObject.Parse(json);
string[] results = jsonObject.SelectTokens("results").Select(r => r.ToString()).ToArray();
This will give you an array of strings where each value within the array is the actual json string for each result.
If you however would like to query for the coordinates only:
var jsonObject = JObject.Parse(json);
var coordinates = jsonObject["results"]
.Select(x => x.SelectToken("geometry").SelectToken("location"))
.Select(x => string.Format("{0},{1}", (string)x.SelectToken("lat"), (string)x.SelectToken("lng")))
.ToArray();
This would give you an array of coordinates, eg:
[
"-33.867217,151.195939",
"-33.866786,151.195633",
...
]
Whatever approach you choose you'll be able to accomplish same results using either Newtonsoft or the .net serializer, whilst the Newtonsoft approach would allow you to query without creating strong types for deserialization.

I don't find the point of "[...] pass the valid results array from the string to be deserialized".
Maybe you need to switch to JSON.NET and do something like this:
// You simply deserialize the entire response to an ExpandoObject
// so you don't need a concrete type to deserialize the whole response...
dynamic responseEntity = JsonConvert.DeserializeObject<ExpandoObject>(
googlePlacesJson, new ExpandoObjectConverter()
);
// Now you can access result array as an `IEnumerable<dynamic>`...
IEnumerable<dynamic> results = responseEntity.results;
foreach(dynamic result in results)
{
// Do stuff for each result in the whole response...
}

How to properly convert returned JSON to C# class?

I am working with an API that returns data in JSON format (as far as I can tell, this is my first time working with a true API or JSON). I read a bunch about working with JSON in C#, and eventually got the Newtonsoft.Json library. Unfortunately, I am having a hard time converting the response I am receiving into a C# class following the examples that exist in the Newtonsoft documentation.
Here is an example of the data returned by this API:
{"name":{"id":1,"name":"name","pID":1,"revisionDate":1390580000000}}
And heres what I have so far:
public class apiDataObject
{
public long id {get; set;}
public string name { get; set; }
public int pID { get; set; }
public long revisionDate { get; set; }
}
public long getID()
{
try
{
data = WebRequest.Create(baseURL);
retData = data.GetResponse().GetResponseStream();
}
catch (Exception exception)
{
outputBox.AppendText(Environment.NewLine + exception.ToString());
}
retDataReader = new StreamReader(retData);
returnedData = retDataReader.ReadToEnd();
outputBox.AppendText(returnedData);
apiDataObject test = new apiDataObject();
JsonConvert.PopulateObject(returnedData, test);
return test.id;
}
I have also tried replacing the JsonConvert.PopulateObject(returnedData, test) with:
apiDataObject test = JsonConvert.DeserializeObject<apiDataObject>(returnedData)
The problem is that my "test" object is always empty after the code finishes. I have stepped through the code, and everything works great until I get to the lines where the test object is created, and supposedly populated. I also tried the inbuilt Microsoft libraries and had the exact same issue. I am honestly stumped, I have spent 2 or 3 hours looking at these few lines of code and tons of documentation and samples of the Newtonsoft.Json library, but simply cant figure out where I've gone wrong here. Any help would be greatly appreciated.

From the JSON you posted, its actually a dictionary type: I changed your method to show you, I tested it out and it works.
public long GetID()
{
var testDict = new Dictionary<string, apiDataObject>();
var returnedData = "{\"name\":{\"id\":1,\"name\":\"name\",\"pID\":1,\"revisionDate\":1390580000000}}";
JsonConvert.PopulateObject(returnedData, testDict);
return testDict["name"].id;
}
Running your original code throws an exception telling you that it doesn't know what to do with the first "name".

Just in case anyone ever comes across this in a search, I figured out an alternative solution to working with this type of data as well. The Newtonsoft.Json library contains a function called DeserializeObject. So for the sample data of:
{"name":{"id":1,"name":"name","pID":1,"revisionDate":1390580000000}}
You can create an object that looks like:
public class Name
{
public int id { get; set; }
public string name { get; set; }
public int pID { get; set; }
public long revisionDate { get; set; }
}
public class RootObject
{
public Name name { get; set; }
}
and then use:
JsonConvert.DeserializeObject<RootObject>(returnedData);
to convert the json into the object without having to use a dictionary.
This is probably "common knowledge", considering the object code can easily be created using the json2csharp converter someone linked earlier, but I was unable to find any direct explanation about when to use the DeserializeObject function or why it should be used versus PopulateObject.

JSON Deserialization in .NET

I've had a look at a few threads but what I'm aiming for I can't seem to find.
I have the following JSON strings returned:
On success:
{"success":{"username":"key"}}
On Error:
{"error":{"type":101,"address":"/","description":"link button not pressed"}}
I need to be able to de-serialize these into a class and determine whether I've got an error or a success message to carry on doing it. Any ideas on how to achieve this?
thanks,
Adam

No need to declare a lot of tiny classes. dynamic keyword can help here.
dynamic jObj = JObject.Parse(json);
if (jObj.error!= null)
{
string error = jObj.error.description.ToString();
}
else
{
string key = jObj.success.username.ToString();
}

One option is to use http://nuget.org/packages/newtonsoft.json - you can either create your own custom class to deserialize into or use dynamic as the target type.
var result = JsonConvert.DeserializeObject<Result>(jsonString);
class Result
{
public SuccessResult success { get; set; }
public ErrorResult error { get; set; }
}
class SuccessResult
{
public string username { get; set; }
}
class ErrorResult
{
public int type { get; set; }
public string address { get; set; }
public string description { get; set; }
}
If you need just to check for success, it is possible to just check result.StartsWith("{\"success\":") to avoid unnecessary parsing. But this should only be done if you have guarantee that the JSON string will always be exactly like this (no extra whitespaces etc.) - so it is usually only appropriate if you own the JSON generation yourself.

This answer covers most options, including rolling your own parser and using JSON.Net:
Parse JSON in C#
You could also just write a regex if the format is going to be that simple...