Simply declaring something as dynamic
doesn't guarantee that the resulting concrete object implements IDynamicMetaObjectProvider
and allows for runtime definition of properties. Rather, dynamic
simply means an object
to which all compile-time checking has been turned off, and so all method and member references to it will be resolved in runtime. See:
Now, when you deserialize a JSON object to a member declared as dynamic
with Json.NET, Newtonsoft will chose JObject
as the concrete type to which to deserialize. As its base type JToken
implements IDynamicMetaObjectProvider
you can do things like requestBody.Attributes.Name
and the .Net runtime will forward the property resolution to the JObject
which will look the property up inside its list of properties. However, this doesn't happen automatically, Newtonsoft had to enhance JToken
to make dynamic property access possible.
System.Text.Json
, however, does not have built-in support for deserializing free-form JSON to some custom type implementing IDynamicMetaObjectProvider
, so you will need to use the compile-time methods of the actual type returned, viz. JsonElement
, to access the JSON data contained therein:
var name = requestBody.Attributes.GetProperty("Name").ToString();
Or, you could cast it for clarity:
var name = ((JsonElement)requestBody.Attributes).GetProperty("Name").ToString();
Demo fiddle here.
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