system-text-json-net11
Imperative guidance for the System.Text.Json APIs added in .NET 11: the built-in `JsonNamingPolicy.PascalCase` naming policy, and the strongly-typed `JsonSerializerOptions.GetTypeInfo<T>()` and `JsonSerializerOptions.TryGetTypeInfo<T>(out JsonTypeInfo<T>? info)` metadata accessors. USE ONLY when the user is targeting net11.0 or later and needs PascalCase JSON property or dictionary-key names without writing a custom naming policy, a strongly-typed `JsonTypeInfo<T>` instead of the non-generic `JsonTypeInfo`, or a no-throw way to probe whether a type's serialization metadata is resolved. DO NOT USE when the target is earlier than net11.0, the requested behavior uses an established pre-net11 naming policy, or the user explicitly selected another JSON library.
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System.Text.Json — .NET 11
New APIs added to System.Text.Json across .NET 11 releases.
When to Use
- Serializing or deserializing JSON in a .NET 11 (or later) project
- Needing strongly-typed
JsonTypeInfo<T>access instead of the untypedJsonTypeInfooverload - Wanting to safely check whether type metadata is available without catching exceptions (
TryGetTypeInfo<T>) - Requiring PascalCase property naming during JSON serialization
When Not to Use
- The project targets .NET 10 or earlier — these APIs are not available before .NET 11
- Using a JSON library that is not
System.Text.Json(e.g., Newtonsoft.Json) - The existing untyped
GetTypeInfo(Type)/TryGetTypeInfo(Type, ...)overloads are sufficient
Target Framework
<TargetFramework>net11.0</TargetFramework>
New APIs
Typed JsonTypeInfo Access
JsonSerializerOptions.GetTypeInfo<T>()
Returns a strongly-typed JsonTypeInfo<T> for the specified type, using the
options' configured type-info resolver.
JsonTypeInfo<T> GetTypeInfo<T>()
JsonSerializerOptions.TryGetTypeInfo<T>(out JsonTypeInfo<T>?)
Attempts to retrieve typed metadata without throwing if the type is not resolved.
bool TryGetTypeInfo<T>(out JsonTypeInfo<T>? typeInfo)
JsonNamingPolicy.PascalCase
A new static property that converts property names to PascalCase during serialization.
static JsonNamingPolicy PascalCase { get; }
Examples
Get Typed JsonTypeInfo
using System.Text.Json;
using System.Text.Json.Serialization.Metadata;
var options = new JsonSerializerOptions(JsonSerializerDefaults.Web);
// Retrieve strongly-typed metadata for MyClass
JsonTypeInfo<MyClass> typeInfo = options.GetTypeInfo<MyClass>();
Console.WriteLine($"Type: {typeInfo.Type.Name}");
TryGetTypeInfo for Safe Access
using System.Text.Json;
using System.Text.Json.Serialization.Metadata;
var options = new JsonSerializerOptions(JsonSerializerDefaults.Web);
if (options.TryGetTypeInfo<MyClass>(out var info))
{
Console.WriteLine($"Resolved type info for {info!.Type.Name}");
}
else
{
Console.WriteLine("Type info not available");
}
PascalCase Naming Policy
using System.Text.Json;
var opts = new JsonSerializerOptions
{
PropertyNamingPolicy = JsonNamingPolicy.PascalCase
};
var obj = new { firstName = "John", lastName = "Doe" };
string json = JsonSerializer.Serialize(obj, opts);
Console.WriteLine(json);
// Output: {"FirstName":"John","LastName":"Doe"}
Combined: Serialize with Typed Metadata
using System.Text.Json;
using System.Text.Json.Serialization.Metadata;
var options = new JsonSerializerOptions
{
PropertyNamingPolicy = JsonNamingPolicy.PascalCase
};
JsonTypeInfo<Person> typeInfo = options.GetTypeInfo<Person>();
string json = JsonSerializer.Serialize(new Person("Jane", 30), typeInfo);
Console.WriteLine(json);
// Output: {"Name":"Jane","Age":30}
public record Person(string Name, int Age);