在flurl PostJsonAsync中将枚举序列化为字符串

using Flurl.Http;
using System;
using System.Net.Http;
using System.Threading.Tasks;

public enum Gender
{
    Male,
    Female
}

public class Person
{
    public string Name { get; set; }
    public Gender Gender { get; set; }
}

public class Program
{
    public static async Task Main(string[] args)
    {
        var person = new Person
        {
            Name = "John",
            Gender = Gender.Male
        };

        try
        {
            var response = await "https://api.example.com"
                .AppendPathSegment("persons")
                .PostJsonAsync(person);
            
            if (response.IsSuccessStatusCode)
            {
                Console.WriteLine("Person created successfully!");
            }
            else
            {
                Console.WriteLine("Failed to create person.");
            }
        }
        catch (FlurlHttpException ex)
        {
            Console.WriteLine("An error occurred: " + ex.Message);
        }
    }
}