I am using .NET 4.7, C#, JSON.NET, MVC 5
I have some input JSON:
[
{
"id" : 1
},
{
"id" : 2
},
{
"id" : 3
}
]
This is provided by a 3rd party API
Normally I would use code such as, to deserialize:
var content = await response.Content.ReadAsStringAsync();
JObject json = JObject.Parse(content);
orderList = JsonConvert.DeserializeObject<OrderList>(json.ToString());
However I am finding that:
JObject json = JObject.Parse(content);
Crashes out with the JSON in question. I strongly suspect that the surrounding "[" and "]" is the cause.
I would normally add :
{
items: [
to correct the input JSON.
Is there a better way, to deserialize it, as it seems this input JSON is incomplete although when I test it, it does seem to be valid JSON.
Possibly I should be using JArray instead of JObject?
Thanks in advance.
You are missing commas "," in the JSON. It should be like this:
[
{
"id" : 1
},
{
"id" : 2
},
{
"id" : 3
}
]
And you can deserialize it like that:
var content = await response.Content.ReadAsStringAsync();
var list = JsonConvert.DeserializeObject<List<MyClass>>(content);
Where list is a List<MyClass>
public class MyClass
{
public int id { get; set; }
}
You have 3 options:
Instead of JObject.Parse, use JArray.Parse because the JSON is an array, not an object. This is not the best way to achieve what you want.
Deserialise to a List<T> where T is a concrete class that contains the matching properties of the object. for example:
var result = JsonConvert.DeserializeObject<List<Order>>(json);
This is better, but...
The best option is not to read the HttpClient response as a string in the first place and let the framework do the work for you. You should use the ReadAsAsync<T> extension method. Internally, this uses a stream and is more efficient than first going to string. So for example:
List<Order> orders = await response.Content.ReadAsAsync<List<Order>>();
Related
I am writing a Web API with requirement where need to pass result class property values as array of Json in response of GET request.
Property class which will be passed as a actual result with Ok Status with object. ( I am mocking actual requirement)
public class ABC
{
public string Name {get;set;}
public string Address{get;set;}
}
I am following default JSONfor matter option which are available in dotnet core web api and it is converting all class attribute into single json element.
{
"Person" :
[
{
"Name": "ABCD",
"Address": "INDIA"
}
]
}
My requirement is to have data in Json format with array as below -
{
"Person" :
[
{"Name": "ABCD"},
{"Address": "INDIA"}
]
}
using Newtonsoft.Json;
use this method to convert obj to string:
JsonConvert.SerializeObject(object)
use this method to convert string to obj:
JsonConvert.DeserializeObject(string)
=== Updated my answer to reflect clarified details ===
Solution with Json.Net:
To get the JSON result that you're looking for, you'll need to create a custom serializer or build your JSON object with dynamic JTokens.
Here's an example using a dynamic JObject:
https://dotnetfiddle.net/EyL5Um
Code:
// Create sample object to serialize
var person = new ABC() { Name = "ABC", Address = "India" };
// Build JSON with dynamic JTokens
dynamic jsonObj = new JObject();
var token = new JArray();
token.Add(new JObject(
new JProperty("Name", person.Name)));
token.Add(new JObject(
new JProperty("Address", person.Address)));
jsonObj.Person = token;
// Print result to console
Console.WriteLine(jsonObj.ToString());
Note
In this form, the code above is not a scalable solution. But it should provide you with a starting point to then build up an iterative approach for the data you're working with.
References
Newtonsoft Documentation - Create JSON w/ Dynamic
I want to retrieve a collection of football leagues from an external api. The response from the server comes as shown below:
{
"api": {
"results": 1496,
"leagues": [
{
"league_id": 1,
.....
The returned object constists of an "api" field which hold "results" and "leagues". I would like deserialize the code and map it to League class objects in my code.
var jsonString = await ExecuteUrlAsync(filePath, url);
var results = JsonConvert.DeserializeObject<IEnumerable<LeagueEntity>>(jsonString);
jsonString is correct, but when the program hits second line I get an exception:
Cannot deserialize the current JSON object (e.g. {\"name\":\"value\"}) into type 'System.Collections.Generic.IEnumerable".
I need to get to the "leagues" field in JSON file, and ignore the rest of the response. How to achieve that?
Assuming your LeagueEntity corresponds to the api.leagues[*] objects, you can use JsonConvert.DeserializeAnonymousType() to pick out and deserialize the interesting portions of the JSON:
var leagues = JsonConvert.DeserializeAnonymousType(jsonString,
new { api = new { leagues = default(List<LeagueEntity>) } })
?.api?.leagues;
This avoids the need to create an explicit data model for the api.leagues container objects. It should also be more efficient than pre-loading into a JToken hierarchy, then as a second step selecting and deserializing the api.leagues array.
Demo fiddle here.
(Alternatively, you could auto-generate a complete data model for the entire JSON using one of the answers from How to auto-generate a C# class file from a JSON string.)
All attempts to use JsonUtility.FromJson on a json with nested values fail.
How would you turn the following json into an object without creating a class for every nested value?
{
"Player": {
"Level": 1
},
"Weapons":{
"BasicWeapon": {
"Level": 1
}
}
}
use SimplJson Library Like this
JSONNode node = JSON.Parse( jsonString );
string level= node["Player"]["Level"].Value;
there is also another Library that can Handle that :
https://assetstore.unity.com/packages/tools/input-management/json-net-for-unity-11347
How do I get a specific nested property from a JSON using JObject?
For example i want to get the uri:
{
"embed": {
"uri": "/presets/88930"
...
There's many ways to access the property you're interested in.
Here's one:
String jsonData = "{ 'embed': { 'uri': '/presets/88930'}}";
var jObject = Newtonsoft.Json.Linq.JObject.Parse(jsonData);
Console.WriteLine((string)jObject["embed"]["uri"]);
if your jObject looks like:
var j = JObject.Parse(#"{""embed"": { ""uri"": ""/presets/88930"" } }");
dynamics makes accessing the object pretty easy:
string value = ((dynamic)j).embed.uri.ToString();
I am calling a RESTful service in C# and the result is similar to this:
{
"blabla":1,
"bbb":false,
"blabla2":{
"aaa":25,
"bbb":25,
"ccc":0
},
"I_want_child_list_from_this":{
"total":15226,
"max_score":1.0,
"I_want_this":[
{
"A":"val1",
"B":"val2",
"C":"val3"
},
{
"A":"val1",
"B":"val2",
"C":"val3"
}
...
]
"more_blabla": "fff"
...
}
I want to get the "I_want_this" part as a list of object or JObject
Is there something like
(JObject)responseString["I_want_child_list_from_this"]["I_want_this"]
more generically:
(JObject)responseString["sub"]["sub_sub"]
I am using Newtonsoft.Json
Thanks!
First off, I would create a class that represents the JSON structure returned from the service call. (http://json2csharp.com/ great utility for auto-generating classes from JSON)
Second, if you are not using Newtonsoft.Json library, I would recommending grabbing that library.
Lastly, use Newtonsoft to deserialize the JSON from the service call into the class you created:
var json = Service.GetJson();
var yourDesiralizedJson = JsonConvert.DeserializeObject<YourJsonToCSharpClass>(json);
var listYouWant = yourDesiralizedJson.IWantChildList.IWantThis;
The below link is appears to be close to the solution as the requester using NewtonSoft.Json as his api to manipulate the object. Appreciate the solutions from other users as well.
look at e.g. here newtonsoft.com/json/help/html/SerializingJSONFragments.htm
The best solution (imo) is to define classes that describe your JSON schema then use DeserializeObject, as suggested by ertdiddy. As a shortcut, you can use DeserializeAnonymousType with incomplete definitions of your schema, taking advantage of JSON's leniency. In your case, this code is working for me:
var testDataFromQuestion = #"
{
""blabla"":1,
""bbb"":false,
""blabla2"":{
""aaa"":25,
""bbb"":25,
""ccc"":0
},
""I_want_child_list_from_this"":{
""total"":15226,
""max_score"":1.0,
""I_want_this"":[
{
""A"":""val1"",
""B"":""val2"",
""C"":""val3""
},
{
""A"":""val1"",
""B"":""val2"",
""C"":""val3""
}
],
""more_blabla"": ""fff""
}";
var anonymousDefinitionOfJson = new {
I_want_child_list_from_this = new {
I_want_this = new Dictionary<string, string>[] {}
}
};
var fullDeserializationOfTestData =
JsonConvert.DeserializeAnonymousType(testDataFromQuestion,
anonymousDefinitionOfJson);
var stuffYouWant = insterestingBits.I_want_child_list_from_this.I_want_this;
Console.WriteLine($"The first thing I want is {stuffYouWant[0]["A"]}");
This outputs the expected value "val1". I'm anonymously defining the minimal classes that get just the data you want, then I'm asking Newtonsoft to parse just enough to populate those classes.