Ajax & ASP.NET Core MVC 6..0：在不使用实体框架的情况下通过 ID 获取数据

Question

I am trying to get data in my DataTable by ID, the data row coming from SQL Server to my controller and passing to Jquery-Ajax but After processing in Ajax, I am getting only UNDEFINED in my DataTable View?

Please note: I have used below code successfully in my ASP.Net MVC app but now after upgrading to ASP.NET CORE MVC 6.0 , It is giving only UNDEFINED.

my model:

    public class EmployeesModel
    {
        public int EmployeeId { get; set; }
        public string? Name { get; set; }
        public string? Gender { get; set; }
        public int Age { get; set; }
        public string? Position { get; set; }
        public string? Office { get; set; }
        [Required(ErrorMessage = "Please enter date")]
        public DateTime HiringDate { get; set; }
        public int Salary { get; set; }

    }

My controller

        [HttpGet]
        public JsonResult GetEmpByName(string Name)
        {

            List<EmployeesModel> employeeList = new List<EmployeesModel>();
            string CS = this.Configuration.GetConnectionString("SQLConn");
            using (SqlConnection conn = new SqlConnection(CS))
            {
                SqlCommand cmd = new SqlCommand("SP_GetEmpByName", conn);
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.Add("@EmpName", SqlDbType.NVarChar).Value = Name; //Added Parameter
                conn.Open();

                // Get
                SqlDataReader reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    EmployeesModel employee = new EmployeesModel();

                    employee.EmployeeId = Convert.ToInt32(reader["EmployeeId"]);
                    employee.Name = reader["Name"].ToString();
                    employee.Gender = reader["Gender"].ToString();
                    employee.Age = Convert.ToInt32(reader["Age"]);
                    employee.Position = reader["Position"].ToString();
                    employee.Office = reader["Office"].ToString();
                    employee.HiringDate = Convert.ToDateTime(reader["HiringDate"]);
                    employee.Salary = Convert.ToInt32(reader["Salary"]);

                    employeeList.Add(employee);
                }
            }
            return Json(new { data = employeeList.ToList(), success = true, responsetext = "Added" });
        }

My view

@model IEnumerable<SQLWithoutEF.EmployeesModel>

<div class="form-control">
    <select class="form-select" id="drpList" onchange="getSelectedValue()">
        <option selected disabled>Please Select</option>
        @foreach(var employee in ViewBag.Employees)
        {
        <option value="@employee.EmployeeId">@employee.Name</option>
        }

    </select>
</div>
  //Here I enter Employee Name and below is button
  
<Button runat="server" Text="Button" class="btn btn-danger" id="IDbtn" onclick="GetByName($('#drpList').val())">Get Data By Name</Button>


@*Data Table ==============*@
<table class="table table-bordered table-responsive table-hover" id="MyTable">
    <thead>
        <tr>
            <th style="display:none">@Html.DisplayNameFor(m => m.EmployeeId)</th>

            <th>@Html.DisplayNameFor(m => m.Name)</th>

            <th>@Html.DisplayNameFor(m => m.Gender)</th>
            <th>@Html.DisplayNameFor(m => m.Age)</th>
            <th>@Html.DisplayNameFor(m => m.Position)</th>
            <th>@Html.DisplayNameFor(m => m.Office)</th>
            <th>@Html.DisplayNameFor(m => m.HiringDate)</th>
            <th>@Html.DisplayNameFor(m => m.Salary)</th>
            <th>Action</th>
        </tr>
    </thead>
    <tbody>
        @foreach (var employee1 in Model)
        {
            <tr>
                <td style="display:none">@employee1.EmployeeId</td>

                <td>@employee1.Name</td>
                <td>@employee1.Gender</td>
                <td>@employee1.Age</td>
                <td>@employee1.Position</td>

                <td>@employee1.Office</td>
                <td>@employee1.HiringDate</td>
                <td>@employee1.Salary</td>
                <td>
                    <asp:button class="btn btn-info btn-xs updbtn1">UpdateEmp</asp:button> |
                    <asp:button class="btn btn-danger btn-xs" data-name="@employee1.Name" id="deletebtn" onclick="deleteF(@employee1.EmployeeId)">DeleteEmp</asp:button>
                </td>
            </tr>
        }
    </tbody>
</table>

My jQuery / Ajax - here I need help: I have tried 3 methods but all fail

 function GetByName(Name) { $('#MyTable tbody tr').remove(); $.ajax({ type: "GET", url: '/Home/GetEmpByName?Name=' + Name, //data: JSON.stringify({ id: id }), commented out //contentType: application/json, charset: utf - 8, commented out //cache: false, commented out processData: false, dataType: 'json', bprocessing: true, success: function (data) { var items = [data.data[0]]; //This line may be wrong, I am not sure. debugger; 3rd try -Failed //let rows = data.map(i=> "<tr><td>" + i.Name + "</td></tr>"); 2nd try -failed // for (var i = 1; i < items.length-1; i++) { // var rows = $('<tr> <td style="Display:none">' + items[EmployeeID] + '</td><td>' + items.data[i].Name + '</td><td>' + items[i][2] + '</td><td>' + items[i][3] + '</td><td>' + items[i][4] + '</td><td>' + items[i][5] + '</td><td>' + items[i][6] + '</td><td>' + items[i][7] + '</td><td>' + items[i][8] + '</td></tr>'); // $('#MyTable tbody').append(rows); // }; // 1st try failed $.each(items, function (index, item) { var rows = ''; rows = `<tr> <td style="Display:none">${item.EmployeeId}</td> <td>${item.Name}</td> <td>${item.Gender}</td> <td>${item.Age}</td> <td>${item.Position}</td> <td>${item.Office}</td> <td>${2020-04-04}</td> <td>${item.Salary}</td> <td><asp:button class="btn btn-info btn-xs updbtn1">UpdateEmp</asp:button> | <asp:button class="btn btn-danger btn-xs" data-name="${item.Name}" id="deletebtn" onclick="deleteF(${item.EmployeeId})">DeleteEmp</asp:button></td> </tr>` $('#MyTable tbody').append(rows); }); }, complete: function () { // setTimeout(function () { // $('.ajaxLoader').hide(); // }, 300); } }).catch(function (xhr, status, error) { var errorMeassage = xhr.status + ': ' + xhr.statusText; alert('Error - ' + errorMeassage); }) }; };

Here is the screenshot what output I am getting

How can I send data from my controller to my DataTable using Ajax?

Answer 1

It's because you return your data with employeeId, name properties but you try to append with EmployeeId, Name . You need to be careful with casing of your object.

rows = `<tr>
<td style="Display:none">${item.employeeId}</td>
<td>${item.name}</td>
<td>${item.gender}</td> ...