在JsonConverter中递归调用JsonSerializer

在JsonConverter中递归调用JsonSerializer

这是一个非常普遍的问题。使用“
JsonConvert.SerializeObject”不是一个坏主意。但是，在某些情况下（通常是集合）可以使用的一个技巧是在写入时将其转换为接口，在读取时将其反序列化为简单的派生。

下面是一个简单的转换器，它处理可能被序列化为一组KVP而不是看起来像对象的字典（在这里显示我的年龄：））

注意“ WriteJson”强制转换为IDictionary ，“ ReadJson”使用“
DummyDictionary”。您最终得到了正确的结果，但是使用了传递的序列化器而不会导致递归。

/// <summary>/// Converts a <see cref="KeyValuePair{TKey,TValue}"/> to and from JSON./// </summary>public class DictionaryAsKVPConverter<TKey, TValue> : JsonConverter{    /// <summary>    /// Determines whether this instance can convert the specified object type.    /// </summary>    /// <param name="objectType">Type of the object.</param>    /// <returns>    ///     <c>true</c> if this instance can convert the specified object type; otherwise, <c>false</c>.    /// </returns>    public override bool CanConvert(Type objectType)    {        if (!objectType.IsValueType && objectType.IsGenericType) return (objectType.GetGenericTypeDefinition() == typeof(Dictionary<,>));        return false;    }    /// <summary>    /// Writes the JSON representation of the object.    /// </summary>    /// <param name="writer">The <see cref="JsonWriter"/> to write to.</param>    /// <param name="value">The value.</param>    /// <param name="serializer">The calling serializer.</param>    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)    {        var dictionary = value as IDictionary<TKey, TValue>;        serializer.Serialize(writer, dictionary);    }    /// <summary>    /// Reads the JSON representation of the object.    /// </summary>    /// <param name="reader">The <see cref="JsonReader"/> to read from.</param>    /// <param name="objectType">Type of the object.</param>    /// <param name="existingValue">The existing value of object being read.</param>    /// <param name="serializer">The calling serializer.</param>    /// <returns>The object value.</returns>    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)    {        Dictionary<TKey, TValue> dictionary;        if (reader.TokenType == JsonToken.StartArray)        { dictionary = new Dictionary<TKey, TValue>(); reader.Read(); while (reader.TokenType == JsonToken.StartObject) {     var kvp = serializer.Deserialize<KeyValuePair<TKey, TValue>>(reader);     dictionary[kvp.Key] = kvp.Value;     reader.Read(); }        }        else if (reader.TokenType == JsonToken.StartObject) // Use DummyDictionary to fool JsonSerializer into not using this converter recursively dictionary = serializer.Deserialize<DummyDictionary>(reader);        else dictionary = new Dictionary<TKey, TValue>();        return dictionary;    }    /// <summary>    /// Dummy to fool JsonSerializer into not using this converter recursively    /// </summary>    private class DummyDictionary : Dictionary<TKey, TValue> { }}