using System;

using System.Text.Json;

using System.Text.Json.Serialization;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        string json = @"{

            ""@timestamp"": [

                ""2022-05-24T01:53:32.600Z""

            ],

            ""site.siteCode"": [

                ""ZAR""

            ],

            ""username"": [

                ""QR02159T1""

            ]

        }";

        JsonSerializerOptions _jsonOptions = new JsonSerializerOptions();

        //_jsonOptions.Converters.Add(new ArrayToSingleConverter());

        var ad4pList = JsonSerializer.Deserialize<Ad4p>(json, _jsonOptions);

        Console.WriteLine(ad4pList.Sitecode);

        Console.WriteLine(ad4pList.Username);

        Console.WriteLine(ad4pList.Timestamp);

    }

}

​

public class ArrayToSingleConverter : JsonConverter<string>

{

​

    public override string Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)

    {

        if (reader.TokenType != JsonTokenType.StartArray)

        {

            throw new JsonException();

        }

​

        List<string> list = new List<string>();

        reader.Read();

        while (reader.TokenType != JsonTokenType.EndArray)

        {

            list.Add(JsonSerializer.Deserialize<string>(ref reader, options));

​

            reader.Read();

        }

        return list.FirstOrDefault();

    }

​

    public override void Write(Utf8JsonWriter writer, string value, JsonSerializerOptions options)

    {

        throw new NotImplementedException();

    }

}

​

public class ArrayToSingleConverter<T> : JsonConverter<T>

{

​

    public override T Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)

    {

        if (reader.TokenType != JsonTokenType.StartArray)

        {

            throw new JsonException();

        }

​

        List<T> list = new List<T>();

        reader.Read();

        while (reader.TokenType != JsonTokenType.EndArray)

        {

            list.Add(JsonSerializer.Deserialize<T>(ref reader, options));

​

            reader.Read();

        }

        return list.FirstOrDefault();

    }

​

    public override void Write(Utf8JsonWriter writer, T value, JsonSerializerOptions options)

    {

        throw new NotImplementedException();

    }

}

​

public class Ad4p

{

    [JsonPropertyName("site.siteCode")]

    [JsonConverter(typeof(ArrayToSingleConverter<string>))]

    public string Sitecode { get; set; }

​

    [JsonPropertyName("username")]

    [JsonConverter(typeof(ArrayToSingleConverter<string>))]

    public string Username { get; set; }

​

    [JsonPropertyName("@timestamp")]

    [JsonConverter(typeof(ArrayToSingleConverter<string>))]

    public string Timestamp { get; set; }

}