How to get all lines of JSON without knowing schema with JsonNode?

Question

Let's say I am expecting a simple JSON response from an API like so:

{
  "message": "Source: ",
  "incomingUrl": "https://10.1.1/api/echo",
  "incomingHeadersCount": 21,
  "apiVersion": "1.0"
}

I can use JsonNode to parse it and output the lines. This requires me to access it by specifying the key:

var parsedJson = JsonNode.Parse(apiResponse.Result);
Console.WriteLine(parsedJson["message"]);

I'd prefer to do something like this where I don't have to know any of the keys:

foreach (var item in parsedJson)
{
    Console.WriteLine(item);
}

This should return, "Source: ", "https://10.1.1/api/echo", "21", "1.0". Is this possible with JsonNode?

JOSEFtw · Answer 1 · 2023-05-15T20:00:37.317

1

Do you need to use JsonNode?

This loops through all properties:

var data = JsonNode.Parse(apiResponse.Result).AsObject();
foreach(var item in data)
{
    var key = item.Key;
    var value = item.Value;
    Console.WriteLine(value);

}

One drawback with this approach is that you'll need to know what type the value is, since you'll need to call .GetValue<T>() on the value. Assuming it's always a string, just call .GetValue<string>(). If you just want to print the value you are fine though.

You could also deserialize directly to a Dictionary<string, string>.

var items = JsonSerializer.Deserialize<Dictionary<string, string>(apiResponse.Result);

foreach(var item in items)
{
    Console.WriteLine(item.Value);
}

If the values are of different types, you could create a custom JsonConverter and deserialize to a Dictionary<string, object>.

edited May 15 '23 at 20:00

answered May 15 '23 at 19:32

JOSEFtw

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I just tried the `JsonSerializer` approach. It fails to serialize it into a string. I'm guessing because "incomingHeadersCount" is an `int`? If that's how it is supposed to work, that is fine. I can work around it. Just want to make sure – AlbatrossCafe May 15 '23 at 19:50
Ah sorry thought that it was all string values...yeah an Int can't be stored in a Dictionary – JOSEFtw May 15 '23 at 19:54
1

You could add a custom JsonConverter and deserialize to a Dictionary https://josef.codes/custom-dictionary-string-object-jsonconverter-for-system-text-json/ – JOSEFtw May 15 '23 at 19:55

Serge · Answer 2 · 2023-05-15T20:37:54.370

the simpliest way is to use linq

List<JsonValue> data = JsonNode.Parse(apiResponse.Result).AsObject()
                               .AsEnumerable().Select(d => d.Value.AsValue())
                               .ToList();

and to display

Console.WriteLine(string.Join(", ", data));

output

Source: , https://10.1.1/api/echo, 21, 1.0

or to Dictionary

Dictionary<string,string> dict = JsonNode.Parse(apiResponse.Result).AsObject()
                                         .ToDictionary(d => d.Key, 
                                                       d => d.Value.ToString());
                               
 Console.WriteLine(dict["message"]); // "source: "

How to get all lines of JSON without knowing schema with JsonNode?

2 Answers2