Filtering Out Properties in an ASP.NET Core API

Question

I want to serve up the following JSON in my API:

{
  \"id\": 1
  \"name\": \"Muhammad Rehan Saeed\",
  \"phone\": \"123456789\",
  \"address\": {
    \"addre         


        

Answer 1

You can use dynamic with ExpandoObject to create a dynamic object containing the properties you need. ExpandoObject is what a dynamic keyword uses under the hood, which allows adding and removing properties/methods dynamically at runtime.

[HttpGet("test")]
public IActionResult Test()
{
    dynamic person = new System.Dynamic.ExpandoObject();

    var personDictionary = (IDictionary<string, object>)person;
    personDictionary.Add("Name", "Muhammad Rehan Saeed");

    dynamic address = new System.Dynamic.ExpandoObject();
    var addressDictionary = (IDictionary<string, object>)address;
    addressDictionary.Add("PostCode", "AB1 2CD");

    personDictionary.Add("Address", address);

    return Json(person);
}

This results in

{"Name":"Muhammad Rehan Saeed","Address":{"PostCode":"AB1 2CD"}}

You'd just need to create a service/converter or something similar that will use reflection to loop through your input type and only carry over the properties you specify.