var builder = WebApplication.CreateBuilder(args);

builder.Services.Configure<MvcOptions>(options =>
{
     options.AllowEmptyInputInBodyModelBinding = true;
});

public IActionResult Post([FromBody(EmptyBodyBehavior = EmptyBodyBehavior.Allow)] MyBody? body)
{
   // body will be null if the request Content-Length == 0
}

public class ExampleController : Controller
{
    public IActionResult Post(MyBody? body) // Nullable
    {
        // body will be null if the request Content-Length == 0
    }
    
    public IActionResult Post(MyBody body) // Non-nullable
    {
        // Request will fail with a 400 and "A non-empty request body is required."
        // when Content-Length == 0
    }
}

[HttpGet(Name = "GetWeatherForecast")]
public IResult Get()
{
    return Results.Ok(new { Name = "My name" });
}

{
  "value": {
    "name" : "My name"
  },
  "statusCode" : 200,
  "contentType" : null
}

{
   "name" : "My name"
}

public class OldCarDto
{
    public string Brand { get; set; }
    public string Model { get; set; }
    public uint Horsepower { get; set; }
}

var json = """
[
  {
    "brand": "Ferrari",
    "horsePower": 651
  },
  {
    "model": "F50",
    "horsePower": 512
  }
]
""";

var options = new JsonSerializerOptions
              {
                  PropertyNameCaseInsensitive = true,
                  PropertyNamingPolicy = JsonNamingPolicy.CamelCase
              };

var oldResults =  JsonSerializer.Deserialize<List<OldCarDto>>(json, options);

public class NewCarDto
{
    public required string Brand { get; init; }
    public required string Model { get; init; }
    public required uint Horsepower { get; init; }
}

var newResults =  JsonSerializer.Deserialize<List<NewCarDto>>(json, options);

System.Text.Json.JsonException: JSON deserialization for type 'NewCarDto'
was missing required properties, including the following: model

var registration = NavigationManager.RegisterLocationChangingHandler(async cxt =>
{
    if (cxt.TargetLocation.EndsWith("counter"))
    {
        cxt.PreventNavigation();
    }
});

<NavigationLock OnBeforeInternalNavigation="ConfirmNavigation" ConfirmExternalNavigation />

<EditForm EditContext="editContext" OnValidSubmit="Submit">
    ...
</EditForm>
<NavigationLock OnBeforeInternalNavigation="ConfirmNavigation" ConfirmExternalNavigation />

    @code {
        private readonly EditContext editContext;
        ...

        // Called only for internal navigations.
        // External navigations will trigger a browser specific prompt.
        async Task ConfirmNavigation(LocationChangingContext context)
        {
            if (editContext.IsModified())
            {
                var isConfirmed = await JS.InvokeAsync<bool>("window.confirm", 
                   "Are you sure you want to leave this page?");
                
                if (!isConfirmed)
                {
                    context.PreventNavigation();
                }
            }
        }
    }