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ReadAsAsync JSON with non-static datamodels into model

The following is a model based on the response from an API (using sample data):
public class SchoolInfoModel
{
public string Name { get; set; }
public string Website { get; set; }
public Address Address { get; set; }
public List<SchoolTypeModel> SchoolTypes { get; set; }
}
The SchoolTypeModel is where I'm stuck. The SchoolType will return a list but the content of the list might contain one other model or two other models or more. Basically a list of a number of different models. But I do not know in advance which models I receive. How do I map these?
Examples of "SchoolType" models I can receive:
public class HighSchoolModel
{
public string Type { get; set; }
public string SubName { get; set; }
public bool BA { get; set; }
public bool CP { get; set; }
public bool HU { get; set; }
public bool MN { get; set; }
public bool TI { get; set; }
}
public class SpecialPurposeSchoolModel
{
public string Type { get; set; }
public string SubName { get; set; }
public bool AH { get; set; }
}
I have a total of about 10 different types of school.

Here's a way you can achieve this with JSON.Net (which means it will work in .NET Framework 4.8). You can create a custom converter to figure out what properties exist in this JSON and use that to determine which type to deserialise to. For example:
public class SchoolTypeConverter : JsonConverter
{
public override bool CanConvert(Type objectType)
=> objectType == typeof(SchoolTypeModel);
public override object ReadJson(JsonReader reader, Type objectType, object existingValue,
JsonSerializer serializer)
{
JObject obj = JObject.Load(reader);
if (obj.ContainsKey("AH"))
{
return obj.ToObject<SpecialPurposeSchoolModel>(serializer);
}
if (obj.ContainsKey("BA"))
{
return obj.ToObject<HighSchoolModel>(serializer);
}
// We have no idea what this is, so panic
throw new Exception("No idea what to do with this value!");
}
public override void WriteJson(JsonWriter writer, object value,
JsonSerializer serializer)
{
// We are only using this to read JSON
throw new NotImplementedException();
}
}
And to read the JSON:
var settings = new JsonSerializerSettings();
settings.Converters.Add(new SchoolTypeConverter());
var result = JsonConvert.DeserializeObject<SchoolInfoModel>(yourJsonString,
settings); // Pass in the settings object we created above

Deserialize Object List Json

I'm new in C# and I want to get a JSON from my app in heroku. Before I did it in javascript with no problems but I'm triying to do it in C# now.
My code is:
namespace FirstApp
{
public class AOA
{
public Data data { get; set; }
public static void Main()
{
var json = string.Empty;
var aoa = new List<AOA>();
try
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(#"http://beautyglam.herokuapp.com/aoa/eyeliner?page=1");
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream stream = response.GetResponseStream();
StreamReader reader = new StreamReader(stream);
json = reader.ReadToEnd();
aoa = JsonConvert.DeserializeObject<List<AOA>>(json);
Console.WriteLine("DATOS");
Console.WriteLine(json);
Console.WriteLine(aoa[0].data);
}
catch(Exception e)
{
Console.WriteLine("Errorrr: " + e);
}
}
}
public class Data
{
public string category { get; set; }
public int pages { get; set; }
public string name { get; set; }
public int? price { get; set; }
public string id { get; set; }
public string img { get; set; }
}
}
The returned json is something like:
[{"category":"AOA Eye Liner","pages":0},{"name":"AOA Starlet Eyeliner- Spotlight","price":150,"id":"751612657678","img":"//cdn.shopify.com/s/files/1/0882/6874/products/AOA-164-MAIN_large.jpg?v=1539192189"},{"name":"AOA Starlet Eyeliner- Hollywood","price":150,"id":"751612592142","img":"//cdn.shopify.com/s/files/1/0882/6874/products/AOA-166-MAIN_large.jpg?v=1539192156"},{"name":"AOA Starlet Eyeliner- Fame","price":150,"id":"751612559374","img":"//cdn.shopify.com/s/files/1/0882/6874/products/AOA-169-MAIN_large.jpg?v=1539192087"},{"name":"AOA Starlet Eyeliner- Superstar","price":150,"id":"751612526606","img":"//cdn.shopify.com/s/files/1/0882/6874/products/AOA-167-MAIN_large.jpg?v=1539192203"},{"name":"AOA Starlet Eyeliner- Paparazzi","price":150,"id":"751612461070","img":"//cdn.shopify.com/s/files/1/0882/6874/products/AOA-165-MAIN_large.jpg?v=1539192338"},{"name":"AOA Starlet Eyeliner- Golden Girl","price":150,"id":"751612329998","img":"//cdn.shopify.com/s/files/1/0882/6874/products/AOA-168-MAIN_large.jpg?v=1539192127"},{"name":"AOA Wonder Liquid Liner - Black","price":150,"id":"194917793806","img":"//cdn.shopify.com/s/files/1/0882/6874/products/AOA-036-1_large.jpg?v=1522944978"},{"name":"AOA Wonder Liquid Liner - Dark Brown","price":150,"id":"194917335054","img":"//cdn.shopify.com/s/files/1/0882/6874/products/AOA-037-1_large.jpg?v=1522944879"}]
I want to use it like in Javascript, for example:
aoa[0].name;

Your class representation of your json structure is not valid for your example. Also, your json structure needs to be parsed with some special deserializer because it is not contains consist values.
You have an array of json object but they are not have same type.
You need 3 classes which one represents category and pages, one represents name,price,id,img and one for the root which containts those two classes.
Here is what it should look like:
class RootObj {
public Category category { get; set; }
public List<Detail> details { get; set; }
}
class Category {
public string category { get; set; }
public int pages { get; set; }
}
class Detail {
public string name { get; set; }
public int price { get; set; }
public string id { get; set; }
public string img { get; set; }
}
Here is custom deserializer:
class CustomObjectConverter<T> : JsonConverter
{
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
throw new NotImplementedException();
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
JArray array = JArray.Load(reader);
RootObj result = new RootObj();
result.category = array[0].ToObject<Category>();
array.RemoveAt(0);
result.details = array.ToObject<List<Detail>>();
return result;
}
public override bool CanConvert(Type objectType)
{
return (objectType == typeof(RootObj));
}
}
Main :
string jsonText = File.ReadAllText("json.txt");
var deserializer = new JsonSerializerSettings();
deserializer.Converters.Add(new CustomObjectConverter<RootObj>());
var result = JsonConvert.DeserializeObject<RootObj>(jsonText, deserializer);
Now you can access the properties as :
Console.WriteLine(result.category.category);
Output is :
AOA Eye Liner
You can customize it according to your use cases.

How to group properties together when serializing to JSON

I have a flat object that I would like to group into sections in order to make parsing it easier. This is the basic idea of what my class currently looks like:
class Populations {
public string US { get; set; }
public string Canada { get; set; }
public string Germany { get; set; }
public string England { get; set; }
}
But this is what I want it to be serialized into when populated with data:
{
"Populations": {
"North America": {
"US": "318 million",
"Canada": "35 million"
},
"Europe": {
"Germany": "80 million",
"England": "53 million"
}
}
}
What I am trying to do is wrap my countries into continents without actually creating new continent classes. Is this possible with a tool like Json.Net or do I simply have to create a NorthAmerica class with two properties and then create a Europe class with two properties? Is it possible an annotation exists to allow me group together some of these properties?

There is no built-in mechanism in Json.Net to do this grouping as you describe; however, you could make a custom JsonConverter to do it if that's what you really want. Something like this might work:
class GroupAttribute : Attribute
{
public string Name { get; set; }
public GroupAttribute(string name)
{
Name = name;
}
}
class GroupingConverter : JsonConverter
{
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
JObject obj = new JObject();
Type type = value.GetType();
foreach (PropertyInfo pi in type.GetProperties())
{
JToken propVal = JToken.FromObject(pi.GetValue(value));
GroupAttribute group = pi.GetCustomAttribute<GroupAttribute>();
if (group != null)
{
JObject groupObj = (JObject)obj[group.Name];
if (groupObj == null)
{
groupObj = new JObject();
obj.Add(group.Name, groupObj);
}
groupObj.Add(pi.Name, propVal);
}
else
{
obj.Add(pi.Name, propVal);
}
}
JObject wrapper = new JObject(new JProperty(type.Name, obj));
wrapper.WriteTo(writer);
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
throw new NotImplementedException();
}
public override bool CanRead
{
get { return false; }
}
public override bool CanConvert(Type objectType)
{
// CanConvert is not called when a [JsonConverter] attribute is applied
return false;
}
}
You would then mark up your Populations class like this:
[JsonConverter(typeof(GroupingConverter))]
class Populations
{
[Group("North America")]
public string US { get; set; }
[Group("North America")]
public string Canada { get; set; }
[Group("Europe")]
public string Germany { get; set; }
[Group("Europe")]
public string England { get; set; }
}
Finally, serialize like this:
string json = JsonConvert.SerializeObject(populations, Formatting.Indented);
Fiddle: https://dotnetfiddle.net/EPiJue

You could create classes NorthAmerica and Europe, or you could do something like:
class Continent{
string Type { get; set; }
ICollection<Country> Countries { get; set; }
}
This would of course necessitate that all your countries have a common base class or interface.

Seeing as how your JSON doesn't have arrays, you're current classes make this json impossible to create unless you create another class with the exact structure you would want or Select it into a dynamic object.
If you must strictly abide by this JSON, I would encourage you to make a different population class that has a structure like
class Populations {
public NorthAmerica NorthAmerica { get; set; }
public Europe Europe { get; set; }
}
class NorthAmerica{
public string US { get; set; }
public string Canada { get; set; }
}
class Europe{
public string Germany{ get; set; }
public string England{ get; set; }
}

newtonsoft.json deserializing logic

I'm trying to parse a json string with for example [1,2,3] to an array during deserializing.
This is my json data:
[
{
"id": "1",
"district": "1",
"lon": "4.420650000000000000",
"lat": "51.21782000000000000",
"bikes": "19",
"slots": "14",
"zip": "2018",
"address": "Koningin Astridplein",
"addressNumber": null,
"nearbyStations": "3,4,5,24",
"status": "OPN",
"name": "001- Centraal Station - Astrid"
}
]
And this is my c# currently mapping to a regular string, which i would like to be an array of integers.
var AvailabilityMap = new[] { new Station() };
var data = JsonConvert.DeserializeAnonymousType(json, AvailabilityMap);
public class Station
{
public int Id { get; set; }
public double Lon { get; set; }
public double Lat { get; set; }
public int Bikes { get; set; }
public int Slots { get; set; }
public string Address { get; set; }
public string NearbyStations { get; set; }
public string Status { get; set; }
public string Name { get; set; }
}
I have found no way so far to do this in a proper way, without looping trough my current array once more..

Create a custom converter. Something like this:
public class StringToIntEnumerable : JsonConverter
{
public override bool CanConvert(Type objectType)
{
throw new NotImplementedException();
}
public override bool CanWrite
{
get
{
return false; // we'll stick to read-only. If you want to be able
// to write it isn't that much harder to do.
}
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
// Note: I've skipped over a lot of error checking and trapping here
// but you might want to add some
var str = reader.Value.ToString();
return str.Split(',').Select(s => int.Parse(s));
}
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
throw new NotImplementedException();
}
}
Now change you class to use the converter by using the JsonConverterAttribute:
public class Station
{
public int Id { get; set; }
public double Lon { get; set; }
public double Lat { get; set; }
public int Bikes { get; set; }
public int Slots { get; set; }
public string Address { get; set; }
[JsonConverter(typeof(StringToIntEnumerable))]
public IEnumerable<int> NearbyStations { get; set; } // or List<int> or int[] if
// you prefer, just make
// sure the convert returns
// the same type
public string Status { get; set; }
public string Name { get; set; }
}
And now to deserialize:
var stations = JsonConvert.DeserializeObject<List<Station>>(json);

Here is a working fiddle that uses a custom JsonConverter.
What we're doing is converting your CSV values into a proper JSON array before we convert the entire JSON string into a Station object.
Custom JsonConverter
ReadJson reads through the JSON string. First, it loads the JSON into a JObject. Next, it gets the nearbyStations property and changes it from a simple CSV string into a JavaScript array. It does this by wrapping the CSV within square brackets. Finally, we use the JsonSerializer to populate our target object and return it.
CanWrite is set to false, because this JsonConverter is only allowed to read JSON not write to JSON. As a result, we don't need to implement WriteJson. The CanConvert tests to make sure that the target object is a Station.
public class StationConverter : JsonConverter
{
public override object ReadJson(
JsonReader r, Type t, object v, JsonSerializer s)
{
JObject jObject = JObject.Load(r);
var prop = jObject.Property("nearbyStations");
var wrapped = string.Format("[{0}]", prop.Value);
JArray jsonArray = JArray.Parse(wrapped);
prop.Value = jsonArray;
var target = new Station();
s.Populate(jObject.CreateReader(), target);
return target;
}
public override void WriteJson(JsonWriter w, object v, JsonSerializer s)
{
throw new NotImplementedException("Unnecessary: CanWrite is false.");
}
public override bool CanWrite
{
get { return false; }
}
public override bool CanConvert(Type objectType)
{
return objectType == typeof (Station);
}
}
Change the Station Class to have an int[]
For the above JsonConverter to to work, change your NearbyStations property to be an int[].
public int[] NearbyStations
{
get;
set;
}
Usage Example with Live Fiddle
Here is an example of how to use it:
var AvailabilityMap =
JsonConvert.DeserializeObject<Station[]>(json, new StationConverter());
Console.WriteLine(AvailabilityMap[0].NearbyStations[0]);

The right answer is to have properly formatted input. In this case:
"nearbyStations": ["3","4","5","24"]
But I was faced with a similar situation in which the data could not be updated, so a solution had to be found. The easiest is to make a getter/setter that won't be touched by the serializer/deserializer. Unfortunately you can't ignore public properties with this serializer out of the box. So you have to do some clever work-arounds like reading into a DTO and using a business object for actual operations.
public class StationDTO
{
public int Id { get; set; }
public double Lon { get; set; }
public double Lat { get; set; }
public int Bikes { get; set; }
public int Slots { get; set; }
public string Address { get; set; }
public string NearbyStations { get; set; }
public string Status { get; set; }
public string Name { get; set; }
}
...
public class Station : StationDTO
{
public List<string> NearbyStationsList
{
get
{
return NearbyStations.Split(',');
}
set
{
NearbyStations = string.Join(",", value);
}
}
}
More information: Newtonsoft ignore attributes?

Custom Json Serialization of class

I have code structured like below.
public class Stats
{
public string URL { get; set; }
public string Status { get; set; }
public string Title { get; set; }
public string Description { get; set; }
public int Length { get; set; }
}
and
public class UrlStats
{
public string URL { get; set; }
public int TotalPagesFound { get; set; }
public List<Stats> TotalPages { get; set; }
public int TotalTitleTags { get; set; }
public List<Stats> TotalTitles { get; set; }
public int NoDuplicateTitleTags { get; set; }
public List<Stats> DuplicateTitles { get; set; }
public int NoOverlengthTitleTags { get; set; }
public List<Stats> OverlengthTitles { get; set; }
}
Basically i am scanning a website for statistics like title tags, duplicate titles, etc.
I am using JQuery and making AJAX calls to webservice and retrieving url stats while the process is running to show user url stats by far collected since it takes quite a time to scan a big website. So after every 5 seconds i retrieve stats from server. Now the problem is all the List variable data i need to send at the end when scanning processing is complete, not during updates. What's happening right now the List<Stats> variable data is also sent during updates which is big chunk of data and i want to send only int type variables which are required to show process updates.
From searching on internet i couldn't find anything useful solving my problem and i found that Json.NET is very good library but i really don't know how to properly use it to get what i want.
Basically i am looking for serializing properties depending on their datatype at runtime, if its possible.

There are two different approaches for your problem.
You should choose the first one if you are going to change your classes more often because the first approach prevents that you forget to serialize a newly added property. Furthermore it is much more reusable if you want to add another classes you want to be serialized the same way.
If you have only these two classes and it's most likely that they're not going to change you can choose the second approach to keep your solution simple.
1. Use a custom converter to select all int properties
The first approach is to use a custom JsonConverter which serializes a class or struct by only including properties which have type int. The code might look like this:
class IntPropertyConverter : JsonConverter
{
public override bool CanConvert(Type objectType)
{
// this converter can be applied to any type
return true;
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
// we currently support only writing of JSON
throw new NotImplementedException();
}
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
if (value == null)
{
serializer.Serialize(writer, null);
return;
}
// find all properties with type 'int'
var properties = value.GetType().GetProperties().Where(p => p.PropertyType == typeof(int));
writer.WriteStartObject();
foreach (var property in properties)
{
// write property name
writer.WritePropertyName(property.Name);
// let the serializer serialize the value itself
// (so this converter will work with any other type, not just int)
serializer.Serialize(writer, property.GetValue(value, null));
}
writer.WriteEndObject();
}
}
Then you have to decorate your class with a JsonConverterAttribute:
[JsonConverter(typeof(IntPropertyConverter))]
public class UrlStats
{
// ...
}
Disclaimer: This code has been tested only very roughly.
2. Choose properties individually
The second solution looks a bit simpler: You can use the JsonIgnoreAttribute to decorate the attributes you want to exclude for serialization. Alternatively you can switch from "blacklisting" to "whitelisting" by explicitly including the attributes you want to serialize. Here is a bit of sample code:
Blacklisting: (I've reordered the properties for a better overview)
[JsonObject(MemberSerialization.OptOut)] // this is default and can be omitted
public class UrlStats
{
[JsonIgnore] public string URL { get; set; }
[JsonIgnore] public List<Stats> TotalPages { get; set; }
[JsonIgnore] public List<Stats> TotalTitles { get; set; }
[JsonIgnore] public List<Stats> DuplicateTitles { get; set; }
[JsonIgnore] public List<Stats> OverlengthTitles { get; set; }
public int TotalPagesFound { get; set; }
public int TotalTitleTags { get; set; }
public int NoDuplicateTitleTags { get; set; }
public int NoOverlengthTitleTags { get; set; }
}
Whitelisting: (also reordered)
[JsonObject(MemberSerialization.OptIn)] // this is important!
public class UrlStats
{
public string URL { get; set; }
public List<Stats> TotalPages { get; set; }
public List<Stats> TotalTitles { get; set; }
public List<Stats> DuplicateTitles { get; set; }
public List<Stats> OverlengthTitles { get; set; }
[JsonProperty] public int TotalPagesFound { get; set; }
[JsonProperty] public int TotalTitleTags { get; set; }
[JsonProperty] public int NoDuplicateTitleTags { get; set; }
[JsonProperty] public int NoOverlengthTitleTags { get; set; }
}

Oh got it, re-reading your question I think you can serialize a projection of your data.
You can try the following:
var json = JsonConvert.SerializeObject(new { u.TotalPagesFound, u.TotalTitleTags, u.NoDuplicateTitleTags, u.NoOverlengthTitleTags } );
This will convert to JSON only the int properties of your class. This is the easiest way, and it is tied to the structure of your class. If you want something more general, you will need to implement a custom converter.
Original answer:
I see no problem with your classes, you don't have anything weird like loop references, so Json.NET should have no problem serializing your class. So go grab Json.NET and then you can attempt the following
// create new instance of your url stat class
var u = new UrlStats() { URL = "a.com", TotalPages = new List<Stats>() { new Stats() { URL = "b.com", Status = "xxxx" } } };
// seralize!
var json = JsonConvert.SerializeObject(u);
Console.Write(json);
What I get with this method is something like this:
{"URL":"a.com","TotalPagesFound":0,"TotalPages":[{"URL":"b.com","Status":"xxxx","Title":null,"Description":null,"Length":0}],"TotalTitleTags":0,"TotalTitles":null,"NoDuplicateTitleTags":0,"DuplicateTitles":null,"NoOverlengthTitleTags":0,"OverlengthTitles":null}
And that looks like good json to me.