Cannot access child value on Newtonsoft.Json.Linq.JProperty -Error happens while checking JObject using LinQ

I have a JObject object which has Json data. I need to collect all KeyValuePairs of whichever has "state": true. Before I read the value, I want to make sure that the JObject has at least one KeyValuePairs with JToken (Value) has "state": true.
Below is my JSON:

{ "AAA": { "state": false, "version": "1.1.14202.0", "result": null, "update": "20171018" }, "BBB": { "state": true, "version": "3.10.1.18987", "result": null, "update": "20171018" }, "CCC": { "state": true, "version": "1.1.1.2", "result": null, "update": "20171018" } } 

And the below is the code currently I'm checking with, which is throwing an exception saying Cannot access child value on Newtonsoft.Json.Linq.JProperty:

JObject jsonData = //JSON data; List<JToken> tokens = jsonData .Children().ToList(); if (tokens.Any(each => each["state"].ToString().ToLower().Contains("true"))) { List<JToken> tokensWithStateTrue = tokens.Where(each => each["state"].ToString().ToLower().Contains("true")).ToList(); } 

Please help me and correct the LinQ statement to read only JTokens with state as true.

1 Answer

This worked for me, looks like you're missing an extra call to Children() to access the properties you need.

//parse JSON and grab it's children. var jsonData = JObject.Parse(json).Children(); List<JToken> tokens = jsonData .Children().ToList(); 

or

List<JToken> tokens = jsonData .Children().Children().ToList(); if (tokens.Any(each => each["state"].ToString().ToLower().Contains("true"))) { List<JToken> tokensWithStateTrue = tokens.Where(each => each["state"].ToString().ToLower().Contains("true")).ToList(); } 

Alternatively you could do this. The code below will return a dictionary with only your states with true values. Otherwise, it will return an empty dictionary if you have no true values.

var dictionaryTokensWithTrueValues = jsonData.Children() .Select(u => u as JProperty) .Where(v => v.Value["state"].ToString().ToLower().Contains("true")) .ToDictionary(k => k.Name, v => v.Value); //check if you have any true values if (dictionaryTokensWithTrueValues.Count() > 0) { //do something with true states here var accessBBB = dictionaryTokensWithTrueValues["BBB"]; //{{"state": true,"version": "3.10.1.18987","result": null,"update": "20171018"}} } else { //no true states. Do something else }