Deserialize JSON with variable property names

Question

I would like to desierialze the json from here.

Similar to this:

{
"BW": {
    "Neujahrstag": {
        "datum": "2017-01-01",
        "hinweis": ""
    },
    "Heilige Drei K\u00f6nige": {
        "datum": "2017-01-06",
        "hinweis": ""
    },
    "Gr\u00fcndonnerstag": {
        "datum": "2017-04-13",
        "hinweis": "Gem\u00e4\u00df \u00a7 4 Abs. 3 des Feiertagsgesetzes von Baden-W\u00fcrttemberg[10] haben Sch\u00fcler am Gr\u00fcndonnerstag und am Reformationstag schulfrei. In der Regel legt das Kultusministerium die Ferientermine so fest, dass diese beiden Tage in die Osterferien bzw. in die Herbstferien fallen."
    },
    "Karfreitag": {
        "datum": "2017-04-14",
        "hinweis": ""
    }
},
"BY": {
    "Neujahrstag": {
        "datum": "2017-01-01",
        "hinweis": ""
    },
    "Heilige Drei K\u00f6nige": {
        "datum": "2017-01-06",
        "hinweis": ""
    }
}

}

I would like to deserialize into this:

public class Root
{
    public State[] States { get; set; }
}

public class State
{        
    public Holiday[] Holidays { get; set; }
}

public class Holiday
{
    public DateTime Date { get; set; }
    public string Note { get; set; }
}

But since the propertynames are not fixed I am not able to do this.

I've also tried using JObject.Parse() but that did not help me alot.

Any idea on how to do this ?

@AluanHaddad I was not able to access the properties and fill my structure from it. — Felix D., Nov 27 '17 at 09:42
@Nkosi sadly `DeserializeObject` does return `null` even with a nested Dictiorary — Felix D., Nov 27 '17 at 09:49
Note that your original source has dates like "0-01-06", which Json.NET will not be able to parse into `DateTime`. — Evk, Nov 27 '17 at 09:55

score 9 · Accepted Answer · answered Nov 27 '17 at 09:51

If you modify your model to this:

public class Root : Dictionary<string, State> { }

public class State : Dictionary<string, Holiday> { }

public class Holiday {
    [JsonProperty(PropertyName = "datum")]
    public DateTime Date { get; set; }

    [JsonProperty(PropertyName = "hinweis")]
    public string Note { get; set; }
}

You can deserialize using this:

var root = JsonConvert.DeserializeObject<Root>(str);
var firstBwHoliday = root["BW"]?["Neujahrstag"].Date;

score 3 · Answer 2 · answered Nov 27 '17 at 09:52

First update the Holiday to handle the property names

public class Holiday {
    [JsonProperty("datum")]
    public DateTime Date { get; set; }
    [JsonProperty("hinweis")]
    public string Note { get; set; }
}

Next you want to deserialize to nested Dictionaries

var rawRoot = JsonConvert.DeserializeObject<Dictionary<string, Dictionary<string, Holiday>>>(json);

Finally you want to traverse the dictionaries to get your final result

var root = new Root {
    States = rawRoot.Select(stateKvp => new State() {
        Holidays = stateKvp.Value.Select(holidayKvp => holidayKvp.Value).ToArray()
    })
    .ToArray()
};

You do however loose the keys as they were not part of your final model.

Deserialize JSON with variable property names

2 Answers2

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