尝试 edit/update 时出现 DBContext 错误

DBContext error when attempting to edit/update

在 jquery/jqgrid table 中执行内联编辑时,我看到 ID (PK) 和列值出现在我的 public IActionResult Edit URL 中有 200 个响应。但是,我随后遇到一个错误,我的 DBContext 不存在,但它与我用来检索数据的 dbcontext 相同。另外,无法 return 字符串消息?在我的编辑工作之前的代码,我做错了什么?

namespace MyProject.Controllers
{
    public class CheckRequestController : Controller
    {
        private readonly MyDBContext _context;

        public CheckRequestController(MyDBContext context)
        {
            _context = context;
        }

        public IActionResult Index()
        {
            return View();
        }

        public IActionResult LoadData()
        {
            try
            {
                var fileData = (from tempFile in _context.CheckRequest
                                select tempFile);
                var data = fileData.ToList();
                return Json(data);
            }
            catch (Exception)
            {
                throw;
            }
        }

        // I'm trying to run an update to the row in SQL Server.  I see my ID and the values come across 200 status but can't update.. Also can't return string from IAction
        // Also can't return string from IActionResult or ActionResult. How to return message if failure
        public IActionResult Edit(CheckRequest checkrequests)
        {
            try
            {
                if (ModelState.IsValid)
                {
                    using (MyDBContext db = new MyDBContext())
                    {
                        db.Entry(checkrequests).State = EntityState.Modified;
                        db.SaveChanges();
                    }
                }
            }
            catch (Exception ex)
            {
                //msg = "Error occured:" + ex.Message;
                var msg = new string[] { "Error occured:" + ex.Message };
            }
            return msg;
        }
    }
}

我删除了只读并且能够跟踪服务器并查看请求;不敢相信我的眼睛没有看到。仍然好奇如何捕获和 return 错误消息,该消息在 IActionResult 中的 return 上很有用。现在我把它改成 return Ok() 所以如果发生错误它就没有用了。