How to Efficiently Retrieve Specific JTokens by Name from a JObject Hierarchy?

Traversing JObject Hierarchy for Specific Token by Name

Problem:

Given a JSON response with a complex hierarchy of JTokens, how can you retrieve a specific JToken by its name efficiently?

Newtonsoft.Json Built-In Function:

Newtonsoft.Json provides the SelectToken() method, which allows direct navigation to a token based on its path. For example:

JToken distance = jObject.SelectToken("routes[0].legs[0].distance.text");

This retrieves the JToken representing the distance text value.

Recursive Search:

If the token's path is not known or you need to find all occurrences of a token with a given name, a recursive search is necessary. Here's a custom helper method for recursive searching:

public static class JsonExtensions
{
    public static List<JToken> FindTokens(this JToken containerToken, string name)
    {
        List<JToken> matches = new List<JToken>();
        FindTokens(containerToken, name, matches);
        return matches;
    }

    private static void FindTokens(JToken containerToken, string name, List<JToken> matches)
    {
        if (containerToken.Type == JTokenType.Object)
        {
            foreach (JProperty child in containerToken.Children<JProperty>())
            {
                if (child.Name == name)
                {
                    matches.Add(child.Value);
                }
                FindTokens(child.Value, name, matches);
            }
        }
        else if (containerToken.Type == JTokenType.Array)
        {
            foreach (JToken child in containerToken.Children())
            {
                FindTokens(child, name, matches);
            }
        }
    }
}

Usage:

string json = @"...", jo = JObject.Parse(json);

foreach (JToken token in jo.FindTokens("text"))
{
    Console.WriteLine(token.Path + ": " + token.ToString());
}

Output:

routes[0].legs[0].distance.text: 1.7 km
routes[0].legs[0].duration.text: 4 mins
routes[0].legs[1].distance.text: 2.3 km
routes[0].legs[1].duration.text: 5 mins

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