无法在Xunit中断言返回jsonresult的ActionResult

using Xunit;
using System.Net.Http;
using Newtonsoft.Json;

namespace YourNamespace.Tests
{
    public class YourTestClass
    {
        private readonly HttpClient _client;

        public YourTestClass()
        {
            var appFactory = new WebApplicationFactory<YourStartupClass>();
            _client = appFactory.CreateClient();
        }

        [Fact]
        public async Task YourTestMethod()
        {
            // 发送HTTP请求
            var response = await _client.GetAsync("/your-api-endpoint");

            // 确保请求成功
            response.EnsureSuccessStatusCode();

            // 读取返回内容
            var responseContent = await response.Content.ReadAsStringAsync();

            // 反序列化为JsonResult对象
            var jsonResult = JsonConvert.DeserializeObject<JsonResult>(responseContent);

            // 对JsonResult对象进行断言
            Xunit.Assert.NotNull(jsonResult);
            Xunit.Assert.Equal("expected-value", jsonResult.Value);
        }
    }
}