What is difference between ObjectResult and JsonResult

JsonResult is an IActionResult which formats the given object as JSON

ObjectResult is an IActionResult that has content negotiation built in.

Inside its ExecuteResultAsync, responsible for writing to the response stream, the framework will walk through the available formatters and select a relevant one.

The logic for choosing a formatter is similar to that in ASP.NET Web API, and based on the following order of precedence:

• Accept header
• Content-Type header
• selection based on type match

OkObjectResult Class

An Microsoft.AspNetCore.Mvc.ObjectResult that when executed performs
content negotiation, formats the entity body, and will produce a
Microsoft.AspNetCore.Http.StatusCodes.Status200OK response if
negotiation and formatting succeed.

References:

• Migrate from ASP.NET MVC to ASP.NET Core MVC
• Asp.Net Documentation: JsonResult Class
• Asp.Net Documentation: ObjectResult Class
• Asp.Net Documentation: OkObjectResult Class