使用Newtonsoft.Json.dll序列化为json时过滤掉NULL值的属性

using Newtonsoft.Json;

namespace WebApi.Controllers

{

    public class Rootobject

    {

        public string PhoneNumber { get; set; }

        public string Name { get; set; }

        public string MF { get; set; }

        public string BirthDate { get; set; }

        public object MaritalStatus { get; set; }

        public object Country { get; set; }

    }

    [Route("api/[controller]/[action]")]

        [ApiController]

        public class ValuesController : ControllerBase

        {

            [HttpGet]

            public IEnumerable<string> Get()

            {