# System.Text.Json.Serialization

``` diff
 namespace System.Text.Json.Serialization {
+    public sealed class JsonSerializableAttribute : JsonAttribute {
+        public JsonSerializableAttribute(Type type);
+        public string TypeInfoPropertyName { get; set; }
+    }
+    public abstract class JsonSerializerContext {
+        protected JsonSerializerContext(JsonSerializerOptions options);
+        public JsonSerializerOptions Options { get; }
+        public abstract JsonTypeInfo GetTypeInfo(Type type);
+    }
+    public enum JsonUnknownTypeHandling {
+        JsonElement = 0,
+        JsonNode = 1,
+    }
 }
```

