从控制器获取结果但 ajax 调用获取错误而不是在 MVC5 和 C# 中成功

我刚刚试图重现你的情况。这里是示例代码。您可以更新您的代码以从我的代码中获取数据库。

您的控制器：

public class ImportFormsController : Controller
    {
        public JsonResult INTImportData(int jobId)
        {
            //if (Session["UserLogon"] != null)
            //{
            BLINTForms objForm = new BLINTForms();
            var objDCFormList = new DCForm.DCFormList();
            //int jobId = Session["Job_ID"] == null ? 0 : (int)Session["Job_ID"];
            //ViewBag.jobId = jobId;

            objDCFormList.Form = objForm.GetINTFormTempDataByJobId(jobId);
            //TempData["DCFormList"] = objDCFormList.Form;
            //Response.StatusCode = (int)HttpStatusCode.OK;
            return Json(objDCFormList.Form, JsonRequestBehavior.AllowGet);
            //}
            //else
            //return Json("Login required", JsonRequestBehavior.AllowGet);

        }

    }

    public class BLINTForms
    {
        public List<DCForm> GetINTFormTempDataByJobId(int jobId)
        {

            List<DCForm> objDCFormList = new List<DCForm>();
            DCForm objDCForm;
            int record = 0;
            try
            {
                for (var i = 0; i < 5; i++)
                {
                    objDCForm = new DCForm();
                    objDCForm.SerialNo = ++record;
                    objDCForm.PayerId = 100;
                    objDCFormList.Add(objDCForm);
                }


                return objDCFormList;
            }
            catch (Exception exce)
            {
                throw exce;
            }
            finally
            {

            }
        }
    }

    public class DCForm : DataOperationResponse
    {
        public int SerialNo { get; set; }
        public int PayerId { get; set; }


        public class DCFormList : DataOperationResponse
        {
            private List<DCForm> _form = null;

            public DCFormList()
            {
                if (_form == null)
                    _form = new List<DCForm>();
            }

            public List<DCForm> Form
            {
                get { return _form; }
                set { _form = value; }
            }
        }
    }

    public class DataOperationResponse
    {
        //public string Message { get; set; }
    }

我在 HomeController:Index 中使用 Index.cshtml 创建了一个测试

<input type="text" id="jobId"/>

<button onclick="GetINTFormTempData($('#jobId').val())">Get Data</button>

<script>

    function GetINTFormTempData(JobId) {
        var result = null;
        $.ajax({
            type: "GET",
            url: '/ImportForms/INTImportData', //**change url**
            data: { jobId: JobId },
            traditional: false,
            success: function(data) {
                result = data;
                alert("JobId");
                alert(JSON.stringify(data));
                LoadINTData(result);
                if (result.length > 0)
                    $(".upload").show();
                else
                    $(".upload").hide();
            },
            error: function(data) {
                alert("fail");
                Success = false;
            }

        });
    }
</script>