KeyValuePairConverter
Converts a KeyValuePair<T, U> to and from JSON.
using Newtonsoft.Json.Serialization;
using Newtonsoft.Json.Utilities;
using System;
using System.Collections.Generic;
namespace Newtonsoft.Json.Converters
{
public class KeyValuePairConverter : JsonConverter
{
private const string KeyName = "Key";
private const string ValueName = "Value";
private static readonly ThreadSafeStore<Type, ReflectionObject> ReflectionObjectPerType = new ThreadSafeStore<Type, ReflectionObject>(InitializeReflectionObject);
private static ReflectionObject InitializeReflectionObject(Type t)
{
Type[] genericArguments = TypeExtensions.GetGenericArguments(t);
Type type = ((IList<Type>)genericArguments)[0];
Type type2 = ((IList<Type>)genericArguments)[1];
return ReflectionObject.Create(t, TypeExtensions.GetConstructor(t, new Type[2] {
type,
type2
}), "Key", "Value");
}
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
ReflectionObject reflectionObject = ReflectionObjectPerType.Get(value.GetType());
DefaultContractResolver defaultContractResolver = serializer.ContractResolver as DefaultContractResolver;
writer.WriteStartObject();
writer.WritePropertyName((defaultContractResolver != null) ? defaultContractResolver.GetResolvedPropertyName("Key") : "Key");
serializer.Serialize(writer, reflectionObject.GetValue(value, "Key"), reflectionObject.GetType("Key"));
writer.WritePropertyName((defaultContractResolver != null) ? defaultContractResolver.GetResolvedPropertyName("Value") : "Value");
serializer.Serialize(writer, reflectionObject.GetValue(value, "Value"), reflectionObject.GetType("Value"));
writer.WriteEndObject();
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
if (reader.TokenType == JsonToken.Null) {
if (!ReflectionUtils.IsNullableType(objectType))
throw JsonSerializationException.Create(reader, "Cannot convert null value to KeyValuePair.");
return null;
}
object obj = null;
object obj2 = null;
reader.ReadAndAssert();
Type key = ReflectionUtils.IsNullableType(objectType) ? Nullable.GetUnderlyingType(objectType) : objectType;
ReflectionObject reflectionObject = ReflectionObjectPerType.Get(key);
JsonContract jsonContract = serializer.ContractResolver.ResolveContract(reflectionObject.GetType("Key"));
JsonContract jsonContract2 = serializer.ContractResolver.ResolveContract(reflectionObject.GetType("Value"));
while (reader.TokenType == JsonToken.PropertyName) {
string a = reader.Value.ToString();
if (string.Equals(a, "Key", StringComparison.OrdinalIgnoreCase)) {
reader.ReadForTypeAndAssert(jsonContract, false);
obj = serializer.Deserialize(reader, jsonContract.UnderlyingType);
} else if (string.Equals(a, "Value", StringComparison.OrdinalIgnoreCase)) {
reader.ReadForTypeAndAssert(jsonContract2, false);
obj2 = serializer.Deserialize(reader, jsonContract2.UnderlyingType);
} else {
reader.Skip();
}
reader.ReadAndAssert();
}
return reflectionObject.Creator(obj, obj2);
}
public override bool CanConvert(Type objectType)
{
Type type = ReflectionUtils.IsNullableType(objectType) ? Nullable.GetUnderlyingType(objectType) : objectType;
if (type.IsValueType() && type.IsGenericType())
return (object)type.GetGenericTypeDefinition() == typeof(KeyValuePair<, >);
return false;
}
}
}