如何在 json object 中获取所有属性的名称（没有它们的值）？

Question

I have a json object, a string, that contains some properties and their values. Say I never know what comes in my json object, how can I loop though it and get what properties it contains? For example:

{ "aaaa": 1, "bbbb": "qwerty", "ccc": 21.22 }

How do I collect aaa, bbb and ccc? Once again, I don't want their values, I just want the name of the properties.

Answer 1

It's as simple as this:

var json = @"{ ""aaaa"": 1, ""bbbb"": ""qwerty"", ""ccc"": 21.22 }";
var jobject = Newtonsoft.Json.Linq.JObject.Parse(json);
var names = jobject.Root.Cast<JProperty>().Select(x => x.Name).ToArray();

That gives:

aaaa
bbbb
ccc

Answer 2

Deserialize the json to Dictionary using JsonConvert

Note: This will work if the key are always unique

var result = JsonConvert.DeserializeObject<Dictionary<string, string>>(jsonString);
Console.WriteLine($"{string.Join(",", result.Keys)}");

Answer 3

just in one line

IEnumerable<string> names = JObject.Parse(json).Properties().Select(x => x.Name);

this will include the names of nested objects properties

IEnumerable names = JObject.Parse(json).Descendants().OfType<JProperty>()
                                                           .Select(x => x.Name);