How-To: Serialize and Deserialize JSON Data

Accessing the serialized and deserialized representation of an object can be important for dynamic, data-rich applications. Uno.Extensions supports the new serialization technique powered by code generation, but you can optionally revert to the previous one which uses reflection.

Step-by-step

Important

This guide assumes you used the template wizard or dotnet new unoapp to create your solution. If not, it is recommended that you follow the Creating an application with Uno.Extensions documentation to create an application from the template.

1. Installation

• Add Serialization to the <UnoFeatures> property in the Class Library (.csproj) file.

  <UnoFeatures>
      Material;
      Extensions;
  +   Serialization;
      Toolkit;
      MVUX;
  </UnoFeatures>
  

2. Opt into Serialization

• Call the UseSerialization() method to register a serializer that implements ISerializer with the service collection:

  protected override void OnLaunched(LaunchActivatedEventArgs e)
  {
      var appBuilder = this.CreateBuilder(args)
          .Configure(host => {
              host
              .UseSerialization();
          });
  ...
  

3. Preparing the class to be serialized efficiently

• Below is a simple Person class which will be serialized to JSON:

  internal class Person
  {
      public Person() { }
  
      public Person(string name, int age, double height, double weight)
      {
          Name = name;
          Age = age;
          Height = height;
          Weight = weight;
      }
  
      public string? Name { get; set; }
      public int Age { get; set; }
      public double  Height { get; set; }
      public double Weight { get; set; }
  }
  

• From .NET 6+, a code generation-enabled serializer is supported. To leverage this in your Uno.Extensions application, define a partial class which derives from a JsonSerializerContext, and specify which type is serializable with the JsonSerializable attribute:

  using System.Text.Json.Serialization;
  
  [JsonSerializable(typeof(Person))]
  internal partial class PersonContext : JsonSerializerContext
  { }
  

• The JsonSerializable attribute will generate several new members on the PersonContext class, allowing you to access the JsonTypeInfo in a static context. Get the JsonTypeInfo for your class using PersonContext.Default.Person and add it within the serializer registration from above:

  protected override void OnLaunched(LaunchActivatedEventArgs e)
  {
      var appBuilder = this.CreateBuilder(args)
          .Configure(host => {
              host
              .UseSerialization(services => services.AddJsonTypeInfo(PersonContext.Default.Person));
          });
  ...
  

4. Configuring the serializer

• The default serializer implementation uses System.Text.Json. The serialization can be configured by registering an instance of JsonSerializerOptions:

  protected override void OnLaunched(LaunchActivatedEventArgs e)
  {
      var appBuilder = this.CreateBuilder(args)
          .Configure(host => {
              host
              .UseSerialization(services =>
              {
                  services.AddJsonTypeInfo(PersonContext.Default.Person);
                  services.AddSingleton(new JsonSerializerOptions { PropertyNameCaseInsensitive = true });
              });
          });
  ...
  

5. Serialize and deserialize JSON data

• Obtain an instance of ISerializer<Person> in the view-model from DI:

  public class MainViewModel
  {
      private readonly ISerializer<Person> jsonSerializer;
  
      public MainViewModel(ISerializer<Person> jsonSerializer)
      {
          this.jsonSerializer = jsonSerializer;
      }
  }
  

• You can now serialize a Person object or deserialize it from JSON:

  Person person = new Person { Name = "Lydia", Age = 24, Height = 160, Weight = 60 };
  string str = jsonSerializer.ToString(person);
  Person newPerson = jsonSerializer.FromString<Person>(str);