Get the path of a key from nested JSON using Json.Net

Question

I have a big nested JSON. I don't know the structure of the JSON. I just have a set of keys which are present in the JSON but I don't know where exactly in the JSON. How do I find out the path of a key from an unknown JSON structure assuming the key exists somewhere in it?

Answer 1

If your JSON structure is unknown, you can parse it into a JToken like this:

JToken token = JToken.Parse(json);

From there, you can use either SelectToken() or SelectTokens() with a recursive descent JsonPath expression to find the property (or properties) matching a key:

JToken match = token.SelectToken("$.." + keyToFind);

Once you have the matching token, you can get the path to it using its Path property:

string path = match?.Path;

Here is a working demo which assumes you have multiple keys to find and each key can appear multiple times in the JSON: https://dotnetfiddle.net/9Em9Iq

Answer 2

For an unknown structure you can iterate over the objects :

var reader = new JsonTextReader(new StringReader(jsonText))
while (reader.Read())
    {
        // Do a condition on the variables reader.TokenType, reader.ValueType, reader.Value

    }

Answer 3

you can use

JObject o = JObject.Parse(<yourjson>);
dynamic obj = o.SelectTokens("$..Product");

Answer 4

This method will log all paths in your top level json that have a key equal to "key"

        var keys = jobject.Properties().Where(p => p.Name == key).ToList();

        keys.ForEach(i => Console.WriteLine(i.Path));

This will NOT work in a recursive way but it is easy from this to do a recursive search from there