使用 Json.net,反序列化包含 Tuple<...>
的类型不起作用(序列化有效,但反序列化无效):
[TestMethod]
public void Test()
{
var orig = new TupleHolder("what????", true);
var json = JsonConvert.SerializeObject(orig);
Assert.AreEqual("{\"Tup\":{\"Item1\":\"what????\",\"Item2\":true}}", json);
// great! serialization works like a charm! now let's test deserialization:
var dupl = JsonConvert.DeserializeObject<TupleHolder>(json);
Assert.AreEqual("ZZZ", dupl.Tup.Item1); // pass! but it should be "what????"... what????
Assert.AreEqual(false, dupl.Tup.Item2); // pass! but it should be "true", right???
Assert.AreEqual(orig.Tup.Item1, dupl.Tup.Item1); // fail!
Assert.AreEqual(orig.Tup.Item2, dupl.Tup.Item2); // fail!
}
public class TupleHolder
{
public Tuple<string, bool> Tup { get; set; }
public TupleHolder() { Tup = new Tuple<string, bool>("ZZZ", false); }
public TupleHolder(string s, bool b) { Tup = new Tuple<string, bool>(s, b); }
}
有趣的是 Tuple<...>
的直接反序列化确实有效:
[TestMethod]
public void Test2()
{
var orig = new Tuple<string, bool>("ABC", true);
var json = JsonConvert.SerializeObject(orig);
var dupl = JsonConvert.DeserializeObject<Tuple<string, bool>>(json);
Assert.AreEqual(orig, dupl); // direct deserialization of Tuple<...> works.
}
这是 Json.NET 错误还是我在这里遗漏了什么?
最佳答案
Remi 提供的答案帮助了我。我拿了他的TupleConverter
并使其成为 2 元组的通用形式。这个概念对于任何 N 元组都是相同的。
我把它留在这里以防它对某人有帮助。
public class TupleConverter<U, V> : Newtonsoft.Json.JsonConverter
{
public override bool CanConvert(Type objectType)
{
return typeof(Tuple<U, V>) == objectType;
}
public override object ReadJson(
Newtonsoft.Json.JsonReader reader,
Type objectType,
object existingValue,
Newtonsoft.Json.JsonSerializer serializer)
{
if (reader.TokenType == Newtonsoft.Json.JsonToken.Null)
return null;
var jObject = Newtonsoft.Json.Linq.JObject.Load(reader);
var target = new Tuple<U, V>(
jObject["m_Item1"].ToObject<U>(), jObject["m_Item2"].ToObject<V>());
return target;
}
public override void WriteJson(Newtonsoft.Json.JsonWriter writer, object value, Newtonsoft.Json.JsonSerializer serializer)
{
serializer.Serialize(writer, value);
}
}
Note: My Tuple was JSON serialized with
m_Item1
andm_Item2
, so I had to changejObject["ItemX"]
tojObject["m_ItemX"]
使用示例 List<Tuple<int, User>>
:
string result = "String to deserialize";
JsonSerializerSettings settings = new JsonSerializerSettings();
settings.Converters.Add(new TupleConverter<int, User>());
List<Tuple<int, User>> users = JsonConvert.DeserializeObject<List<Tuple<int, User>>>(result, settings);
关于c# - Tuple<...> 在另一种类型中的 Json.NET 反序列化不起作用?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27898850/