如何从 JSON 文本中获取反序列化的 C# 对象的类型？

Question

I am trying to get the type of serialized C# object in JSON Text ( $type in JSON text) without deserialising the JSON text to object again . can you please suggest what are all the option do i have?

I am using Newtonsoft library for serialization and serialization.

Thanks in advance

Answer 1

I don't use Newtonsoft library. However, assuming that $type is either at the start of the file or at the end I'd probably use string functions (psudocode below) which'd be quite fast.

• find $type

• i=find next colon

• j=find next comma

• grab token between i and j

• trim that token

• do something useful with the token. Make a type out of it with reflection?

How does that sound? While you are at it you could write an extension method. Hit +1 several times and I'll think about writing the code ;-)

Answer 2

try this

 var jsonObj = JObject.Parse("your json string");
 var props = jsonObj.Properties();

 foreach (var prop in props)
 {
     Console.WriteLine(prop.Value.Type);
 }

I hope this help you!

Answer 3

Its fairly simple using the Newtonsoft library.

JObject json = JObject.Parse(JsonText);
string type = json["$type"].ToString();