ASP.NET

public async Task<IActionResult> Edit(int id, ApplicantViewModel applicant)
    {
        var formerApplicantType = await _context.Applicant
            .Include(a => a.ApplicantTypeNavigation)
            .FirstOrDefaultAsync(m => m.ApplicantId == id);

        if (id != applicant.applicantvm.ApplicantId)
        {
            return NotFound();
        }

        if (ModelState.IsValid)
        {
            try
            {
                if (applicant.applicantvm.ApplicantType == 1)
                {
                    var UpdQuery = from a in _context.Applicant
                                   join p in _context.PersonApplicant on a.ApplicantId
                                   equals p.ApplicantId
                                   where applicant.applicantvm.ApplicantId == a.ApplicantId && applicant.applicantvm.ApplicantType == a.ApplicantType
                                   select new { a, p };

                    if (formerApplicantType.ApplicantType == 2)
                    {
                        Debug.WriteLine("opposite applicantType");

                        var legalApplicantForDelete = await _context.LegalApplicant.FindAsync(id);
                        _context.LegalApplicant.Remove(legalApplicantForDelete);

                        //?????
                        var pa = new PersonApplicant()
                        {
                            BirthCertificateNo = applicant.personapplicantvm.BirthCertificateNo,
                            IssuePlace = applicant.personapplicantvm.IssuePlace,
                            NationalCode = applicant.personapplicantvm.NationalCode,
                            Username = applicant.personapplicantvm.Username,
                            Applicant = applicant.applicantvm
                        };
                        using (var context = new CSSDDashboardContext())
                        {
                            context.PersonApplicant.Add(pa);
                            context.SaveChanges();
                        }
                    }
                    else
                    {


                        //----------------------------------------------
                        foreach (var x in UpdQuery.ToList())
                        {
                            x.a.ApplicantType = applicant.applicantvm.ApplicantType;
                            x.a.Address = applicant.applicantvm.Address;
                            x.a.Description = applicant.applicantvm.Description;
                            x.a.Name = applicant.applicantvm.Name;
                            x.p.BirthCertificateNo = applicant.personapplicantvm.BirthCertificateNo;
                            x.p.NationalCode = applicant.personapplicantvm.NationalCode;
                            x.p.IssuePlace = applicant.personapplicantvm.IssuePlace;
                            x.p.Username = applicant.personapplicantvm.Username;

                        }
                    }

                await _context.SaveChangesAsync();

            }
            catch (DbUpdateConcurrencyException)
            {
                if (!ApplicantExists(applicant.applicantvm.ApplicantId))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }
            return RedirectToAction(nameof(Index));
        }
        ViewData["ApplicantType"] = new SelectList(_context.EntityType, "Id", "Id", applicant.applicantvm.ApplicantType);
        return View(applicant);
    }

Protected Sub DDLbuilding_SelectedIndexChanged(sender As Object, e As EventArgs) Handles DDLbuilding.SelectedIndexChanged
        'Create DataTable
        Dim dtRooms As New DataTable() ' - Room Numbers
        dtRooms.Columns.Add("Room", Type.GetType("System.String"))

        'Get Buildings for this campus
        RoomTable = RoomAdapter.GetRooms(DDLbuilding.SelectedValue)

        'Fill DataTable
        For Each RoomRow In RoomTable
            dtRooms.Rows.Add()
            dtRooms.Rows(dtRooms.Rows.Count - 1)("Room") = RoomRow.Room
        Next

        'bind DDLroom to datatable
        DDLroom.DataSource = dtRooms
        DDLroom.DataBind()
    End Sub

Protected Sub cbEQName_SelectedIndexChanged(sender As Object, e As EventArgs)

     'Get row index of selected comboBox
     Dim gvRow As GridViewRow = CType(CType(sender, Control).Parent.Parent, GridViewRow)
     Dim index As Integer = gvRow.RowIndex

     'Get selected value of selected comboBox
     EQname = TryCast(GVnewEquipment.Rows(index).FindControl("cbEQname"), AjaxControlToolkit.ComboBox).Text

     'Get new values of next comboBox from selected value of selected comboBox
     EquipmentTable = EquipmentAdapter.GetMfg(EQname)

     'Create DataTable
     Dim dtMfgs As New DataTable() ' - mfgs that are used by Equiptment name
     dtMfgs.Columns.Add("mfg", Type.GetType("System.String"))

     'Fill DataTable
     For Each EquipmentRow In EquipmentTable
         dtMfgs.Rows.Add()
         dtMfgs.Rows(dtMfgs.Rows.Count - 1)("mfg") = EquipmentRow.mfg
     Next

     'create ComboBox which will represent GVnewQuipment cbMfg comboBox
     Dim CB = DirectCast(GVnewEquipment.Rows(index).FindControl("cbMfg"), AjaxControlToolkit.ComboBox)

     'bind cbMfg to datatable
     CB.DataSource = dtMfgs
     CB.DataBind()

 End Sub

Hi. I'm implementing asp.net core project. In my controller class I have a query like below that joins two tables.

          var UpdQuery = from a in _context.Applicant
                                       join p in  _context.PersonApplicant on a.ApplicantId
                                       equals p.ApplicantId
                                       where    applicant.applicantvm.ApplicantId == a.ApplicantId // && applicant.applicantvm.ApplicantType == a.ApplicantType
                                       select new { a, p };
                        
I want to get the value of one of Updquery's fields which is called ApplicantType and it is of type int. For doing this, I wrote a query like below to get that value. However it doesn't give me a correct value.

                        var formerApplicantType = UpdQuery.Select(u => u.a.ApplicantType).SingleOrDefault();
                        Debug.WriteLine("formerApplicantType:" + int.Parse(formerApplicantType.ToString()));

I appreciate if any one tells me where do I make a mistake?

Protected Sub txtEmpID_TextChanged(sender As Object, e As EventArgs) Handles txtEmpID.TextChanged
      If String.IsNullOrEmpty(txtEmpID.Text) Then
          checkusername.Visible = False
          Return
      End If

      ' Clear the controls:
      'txtEmpID.Text = String.Empty
      txteName.Text = String.Empty
      txttitle.Text = String.Empty
      txtemail.Text = String.Empty
      lblStatus.Text = String.Empty

      Gridview1.DataSource = Nothing
      Gridview1.DataBind()
      grvspouse.DataSource = Nothing
      grvspouse.DataBind()
      grvDiv.DataSource = Nothing
      grvDiv.DataBind()
      grvReim.DataSource = Nothing
      grvReim.DataBind()
      grvHon.DataSource = Nothing
      grvHon.DataBind()
      grvGift.DataSource = Nothing
      grvGift.DataBind()
      grvOrg.DataSource = Nothing
      grvOrg.DataBind()
      grvCred.DataSource = Nothing
      grvCred.DataBind()

      checkusername.Visible = True
      dprocessed.Visible = True
      lblStatus.ForeColor = System.Drawing.Color.Red

      Using Conn As New SqlConnection(ConfigurationManager.ConnectionStrings("constr").ConnectionString)
          Using cmd As New SqlCommand("ValidateEmpID", Conn)
              cmd.CommandType = CommandType.StoredProcedure
              cmd.Parameters.AddWithValue("@empID", txtEmpID.Text)

              Conn.Open()
              Using dr As SqlDataReader = cmd.ExecuteReader(CommandBehavior.CloseConnection)
                  If Not dr.Read() Then
                      imgstatus.ImageUrl = "images/Icon_Available.gif"
                      lblStatus.Text = "This must be the first time you are completing this form. Proceed to complete entire form. If you feel there is a mistake, please contact the office"
                      txteName.Enabled = True
                      txttitle.Enabled = True
                      txtemail.Enabled = True
                      txtEmpID.Enabled = True
                      GridPanels.Enabled = True
                      btnNext.Enabled = True
                      Return
                  End If

                  imgstatus.ImageUrl = "images/NotAvailable.jpg"
                  txteName.Text = dr("employeeName").ToString()
                  txttitle.Text = dr("empTitle").ToString()
                  txtemail.Text = dr("email").ToString()
                  txtEmpID.Text = dr("empID").ToString()

                  If dr("previousYear").ToString() = "1" Then
                      lblStatus.Text = "Please verify your information for accuracy. Then complete rest of the form."
                      txteName.Enabled = True
                      txttitle.Enabled = True
                      txtemail.Enabled = True
                      txtEmpID.Enabled = True
                      GridPanels.Enabled = True
                      btnNext.Enabled = True
                      fillSourceRecords()

                  ElseIf dr("thisYear").ToString() = "1" Then
                      lblStatus.Text = "You have already completed this form. Please close the form. If you feel there is a mistake, please contact the office"
                      txteName.Enabled = False
                      txttitle.Enabled = False
                      txtemail.Enabled = False
                      txtEmpID.Enabled = False
                      GridPanels.Enabled = False
                      btnNext.Enabled = False

                  Else
                      lblStatus.Text = "No entries this year, nor the previous year. Please complete the form. If you feel this is a mistake, please contact Clerk to the CEO and BOC at 404-371-3224"
                      txteName.Enabled = False
                      txttitle.Enabled = False
                      txtemail.Enabled = False
                      txtEmpID.Enabled = False
                      GridPanels.Enabled = False
                      btnNext.Enabled = False
                  End If
              End Using
          End Using
      End Using
  End Sub

  Private Sub fillSourceRecords()
      Dim conn_str As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString

      Using conn As SqlConnection = New SqlConnection(ConfigurationManager.ConnectionStrings("constr").ConnectionString)
          conn.Open()
          Using sourcecmd As SqlCommand = New SqlCommand()
              sourcecmd.CommandText = "uspGetAllRecs"
              sourcecmd.CommandType = CommandType.StoredProcedure
              sourcecmd.Parameters.AddWithValue("@empID", txtEmpID.Text.Trim())
              sourcecmd.Connection = conn
              Using ad As SqlDataAdapter = New SqlDataAdapter(sourcecmd)
                  Dim ds As DataSet = New DataSet()
                  ad.Fill(ds)
                  Gridview1.DataSource = ds
                  Gridview1.DataBind()
                  grvspouse.DataSource = ds
                  grvspouse.DataBind()
                  grvDiv.DataSource = ds
                  grvDiv.DataBind()
                  grvReim.DataSource = ds
                  grvReim.DataBind()
                  grvHon.DataSource = ds
                  grvHon.DataBind()
                  grvGift.DataSource = ds
                  grvGift.DataBind()
                  grvOrg.DataSource = ds
                  grvOrg.DataBind()
                  grvCred.DataSource = ds
                  grvCred.DataBind()
              End Using
          End Using
      End Using

  End Sub

public partial class InvalidCaseUserControl : System.Web.UI.UserControl
{
    private int _batchNumber;
    private System.ComponentModel.IContainer components = null;
    /// <summary>
    /// Clean up any resources being used.
    /// </summary>
    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
    protected override void Dispose(bool disposing)//Getting 'InvalidCaseUserControl.Dispose(bool)':no suitable method found to override
    {
        if (disposing && (components != null))
        {
            components.Dispose();
        }
        base.Disposed(disposing);
    }
}

protected async void GetCasesButton_Click(object sender, EventArgs e)
{
    //#region Required Field Validation
    if (CaseNumbersTextBox.Text.Length < 1)
    {
        string myStringVariable = "Case number textbox cannot be empty.";
        ClientScript.RegisterStartupScript(this.GetType(), "myalert", "alert('" + myStringVariable + "');", true);
        return;
    }
        try
        {
        #region Get Batch Number
        int newBatchNumber = await CandidateCaseController.GetNextBatchNumber();
        #endregion
        #region Insert entered case numbers in database
			foreach (string caseNumber in userEnteredCaseNumberList)
            {
                EditCandidateCaseModel newCandidate = new EditCandidateCaseModel();
                newCandidate.CaseNbr = caseNumber;
                newCandidate.EntryStaffUserName = Helpers.Authentication.GetADEmail();
                await CandidateCaseController.PostCandidate(newCandidate);
            }
            #region Get MNCIS info on cases
            //candidateCasesString
            List<string> smallEnoughStrings = new List<string>();
            List<AcceptCaseNumbersModel> mncisDetailList = new List<AcceptCaseNumbersModel>();
            List<AcceptCaseNumbersModel> smallEnoughMncisDetailList = new List<AcceptCaseNumbersModel>();
            foreach (string smallEnoughString in smallEnoughStrings)
            {
                smallEnoughMncisDetailList = await FTACaseReseting.Controllers.JusticeController.GetAllAcceptCaseNumbers(smallEnoughString);
                mncisDetailList.AddRange(smallEnoughMncisDetailList);
            }
            #endregion
               
        }
        catch (Exception ex)
        {
            string errorMsg = string.Format("An error has occured in {0}. \nException:\n{1}", "GetCasesButton_Click()", ex.Message);
            ClientScript.RegisterStartupScript(this.GetType(), "myalert", "alert('" + errorMsg + "');", true);
        }
}

public class JusticeController
{
    #region Get
    public static async Task<List<AcceptCaseNumbersModel>> GetAllAcceptCaseNumbers(string candidateCases)
    {
        List<AcceptCaseNumbersModel> retVal = new List<AcceptCaseNumbersModel>();

        TokenModel tm = new TokenModel();
        tm = await TokenController.GetAccessToken();

        if (tm.access_token.Length > 0)
        {
            using (HttpClient client = DataAccess.EstablishConnection(ConfigurationManager.AppSettings.Get("ServiceUri"), ConfigurationManager.AppSettings.Get("ServiceReturnType")))
            {
                client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", tm.access_token);

                HttpResponseMessage response = new HttpResponseMessage();
                response = await client.GetAsync("api/GetAllAcceptCaseNumbers/" + candidateCases);

                if (response.IsSuccessStatusCode)
                    retVal = await response.Content.ReadAsAsync<List<AcceptCaseNumbersModel>>();
            }
        }
        return retVal;
    }
    #endregion
}