StackOverflow Q32847117

CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
					
public class Program
{
	public static void Main()
	{
		ChildDictionary dict = new ChildDictionary();
		dict.Name = "Roster";
		dict.Add(new Employee { Id = 22, Name = "Joe", HireDate = new DateTime(2012, 4, 17) }, 1923.07);
		dict.Add(new Employee { Id = 45, Name = "Fred", HireDate = new DateTime(2010, 8, 22) }, 1415.25);
		
		string json = JsonConvert.SerializeObject(dict, Formatting.Indented);
		Console.WriteLine(json);
		
		dict = JsonConvert.DeserializeObject<ChildDictionary>(json);
		Console.WriteLine("Name: " + dict.Name);
		
		foreach (var kvp in dict)
		{
			Console.WriteLine("Employee Id: " + kvp.Key.Id);
			Console.WriteLine("Employee Name: " + kvp.Key.Name);
			Console.WriteLine("Employee Hire Date: " + kvp.Key.HireDate);
			Console.WriteLine("Amount: " + kvp.Value);
			Console.WriteLine();
		}
	}
}

[JsonConverter(typeof(ComplexDictionaryConverter<Employee, double>))]
public class ChildDictionary : Dictionary<Employee, double>
{
	public string Name { get; set; }
}

public class Employee
{
	public int Id { get; set; }
	public string Name { get; set; }
	public DateTime HireDate { get; set; }
}

public class ComplexDictionaryConverter<K,V> : JsonConverter
{
	public override bool CanConvert(Type objectType)
	{
		return (objectType.GetInterfaces().Any(i => i.IsGenericType && i.GetGenericTypeDefinition() == typeof(IDictionary<K,V>)));
	}
	
	public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
	{
		JObject obj = new JObject();
		foreach (PropertyInfo prop in GetReadWriteProperties(value.GetType()))
		{
			object val = prop.GetValue(value);
			obj.Add(prop.Name, val != null ? JToken.FromObject(val, serializer) : new JValue(val));
		}
		JArray array = new JArray();
		foreach (var kvp in (IDictionary<K, V>)value)
		{
			JObject item = new JObject();
			item.Add("Key", JToken.FromObject(kvp.Key, serializer));
			item.Add("Value", kvp.Value != null ? JToken.FromObject(kvp.Value, serializer) : new JValue(kvp.Value));
			array.Add(item);
		}
		obj.Add("KVPs", array);
		obj.WriteTo(writer);
	}
	
	public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
	{
		JObject obj = JObject.Load(reader);
		IDictionary<K, V> dict = (IDictionary<K, V>)Activator.CreateInstance(objectType);
		foreach (PropertyInfo prop in GetReadWriteProperties(objectType))
		{
			JToken token = obj[prop.Name];
			object val = token != null ? token.ToObject(prop.PropertyType, serializer) : null;
			prop.SetValue(dict, val);
		}
		JArray array = (JArray)obj["KVPs"];
		foreach (JObject kvp in array.Children<JObject>())
		{
			K key = kvp["Key"].ToObject<K>(serializer);
			V val = kvp["Value"].ToObject<V>(serializer);
			dict.Add(key, val);
		}
		return dict;
	}
	
	private IEnumerable<PropertyInfo> GetReadWriteProperties(Type type)
	{
		return type.GetProperties().Where(p => p.CanRead && p.CanWrite && !p.GetIndexParameters().Any());
	}
}