JSON is valid, but result in code returns null

I have this simple JSON 

{
    "persons": [{
        "firstname": "Brad",
        "lastname": "Pitt"
    }, {
        "firstname": "George",
        "lastname": "Clooney"
    }, {
        "firstname": "Matt",
        "lastname": "Damon"
    }]
}

And this are my classes in C#:

public class PersonObject
{
    [JsonProperty(PropertyName = "persons")]
    public List<Person> Persons { get; set; }
}

public class Person
{
    [JsonProperty(PropertyName = "firstname")]
    public string Firstname { get; set; }

    [JsonProperty(PropertyName = "lastname")]
    public string Lastname { get; set; }
}

For some reason it always return null... I really can't see what is wrong with this... With the JsonConvert.DeserializeObject is nothing wrong becouse it works for other JSON strings.

_PersonsList = JsonConvert.DeserializeObject<List<PersonObject>>(data);
Jon Skeet
people
quotationmark

Your data doesn't contain a List<PersonObject> - it contains a single PersonObject which in turn contains a List<Person>. So this works fine:

var json = File.ReadAllText("test.json");
var obj = JsonConvert.DeserializeObject<PersonObject>(json);
Console.WriteLine(obj.Persons[0].Firstname); // Prints Brad

With your current code, you shouldn't be getting a null reference back - you should be getting an exception, like this:

Unhandled Exception: Newtonsoft.Json.JsonSerializationException: Cannot deserialize the current JSON object (e.g. {"name":"value"}) into type 'System.Collections.Generic.List`1[PersonObject]' because the type requires a JSON array (e.g. [1,2,3]) to deserialize correctly.

If you are seeing a null reference, that suggests you're swallowing exceptions somewhere, which is worth fixing separately.

people

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