private void ComboDocNo_TextChanged(object sender, EventArgs e)
 {
     FormatBtnUpdate();
     FormatBtnDelete();
     // Loading data into the form:
     try
     {
         using (DBAuditDataContext dc = new DBAuditDataContext())
         {
             if (ComboDocNo.Text != "")
             {
                 string   StrDocNo      = null;
                 DateTime?VarDatePay    = null;
                 int?     IntLocationID = null;
                 int?     IntEmployeeID = null;
                 string   StrLocation   = null;
                 string   StrEmployee   = null;
                 string   StrPerson     = null;
                 decimal? decimalAmount = null;
                 string   StrDesc       = null;
                 string   StrNotes      = null;
                 var      c             = dc.ProSelectCure(ComboDocNo.Text, ref StrDocNo, ref IntEmployeeID, ref IntLocationID, ref StrPerson, ref decimalAmount, ref VarDatePay, ref StrDesc, ref StrNotes);
                 TxtDocNo.Text = StrDocNo;
                 if (VarDatePay != null)
                 {
                     DatePayDate.Value = VarDatePay.Value;
                 }
                 var d = dc.ProGetLocationByID(IntLocationID, ref StrLocation);
                 ComboLocation.Text = StrLocation;
                 var x = dc.ProGetEmployeeByID(IntEmployeeID, ref StrEmployee);
                 ComboName.Text = StrEmployee;
                 TxtPerson.Text = StrPerson;
                 TxtAmount.Text = decimalAmount.ToString();
                 TxtDesc.Text   = StrDesc;
                 TxtNotes.Text  = StrNotes;
             }
             else
             {
                 TxtDocNo.Text      = "";
                 TxtPerson.Text     = "";
                 ComboLocation.Text = "";
                 TxtAmount.Text     = "";
                 TxtDesc.Text       = "";
                 TxtNotes.Text      = "";
             }
         }
     }
     catch (NullReferenceException)
     {
         BtnDelete.Enabled = false;
     }
     catch (InvalidOperationException)
     {
         BtnDelete.Enabled = false;
     }
     catch (Exception EX)
     {
         MessageBox.Show(EX.Message);
     }
 }
        private void ComboDocNo_TextChanged(object sender, EventArgs e)
        {
            // Formatting the form:
            if (ComboDocNo.Text == "")
            {
                BtnDelete.Enabled = false;
            }
            else
            {
                BtnDelete.Enabled = true;
            }

            if (ComboStatus.Text == "لم يتم تسويتها")
            {
                if (ComboDocNo.Text == "" || ComboLocation.Text == "" || ComboEmployee.Text == "" || TxtTotalAmount.Text == "" || TxtPeriod.Text == "" || TxtReason.Text == "")
                {
                    BtnUpdate.Enabled = false;
                }
                else
                {
                    BtnUpdate.Enabled = true;
                }
            }
            else
            {
                if (ComboDocNo.Text == "" || ComboLocation.Text == "" || ComboEmployee.Text == "" || TxtTotalAmount.Text == "" || TxtPeriod.Text == "" || TxtReason.Text == "" || TxtChequeNo.Text == "" || TxtSettlementAmount.Text == "0")
                {
                    BtnUpdate.Enabled = false;
                }
                else
                {
                    BtnUpdate.Enabled = true;
                }
            }

            // Loading data into the form:
            try
            {
                using (DBAuditDataContext dc = new DBAuditDataContext())
                {
                    if (ComboDocNo.Text != "")
                    {
                        DateTime?VarPayDate              = null;
                        int?     IntLocationID           = null;
                        string   StrLocation             = null;
                        int?     IntEmployeeID           = null;
                        string   StrEmployee             = null;
                        decimal? decimalTotalAmount      = null;
                        int?     IntPeriod               = null;
                        string   StrResason              = null;
                        string   StrStatues              = null;
                        DateTime?varSettlementDate       = null;
                        string   StrChequeNo             = null;
                        DateTime?VarChequeDate           = null;
                        DateTime?VarExpenseDate          = null;
                        DateTime?VarEndDate              = null;
                        decimal? decimalSettlementAmount = null;
                        int?     IntSettlementPEriod     = null;
                        decimal? decimalTax              = null;
                        decimal? decimalPenalty          = null;
                        decimal? decimalFees             = null;
                        decimal? decimalRevenues         = null;
                        decimal? decimalNetAmount        = null;
                        decimal? decimalTotalDiscount    = null;
                        decimal? decimalAmountToPay      = null;
                        decimal? decimalPaidAmount       = null;
                        string   StrBillNo               = null;
                        string   StrSettlementNo         = null;
                        string   StrNotes = null;
                        var      c        = dc.ProSelectTempLoan(ComboDocNo.Text, ref VarPayDate, ref IntLocationID, ref IntEmployeeID, ref decimalTotalAmount, ref IntPeriod, ref StrResason, ref StrStatues, ref varSettlementDate, ref StrChequeNo, ref VarChequeDate, ref VarExpenseDate, ref VarEndDate, ref decimalSettlementAmount, ref IntSettlementPEriod, ref decimalTax, ref decimalPenalty, ref decimalFees, ref decimalRevenues, ref decimalNetAmount, ref decimalTotalDiscount, ref decimalAmountToPay, ref decimalPaidAmount, ref StrBillNo, ref StrSettlementNo, ref StrNotes);
                        DatePayDate.Value = VarPayDate.Value;
                        var d = dc.ProGetLocationByID(IntLocationID, ref StrLocation);
                        ComboLocation.Text = StrLocation;
                        var x = dc.ProGetEmployeeByID(IntEmployeeID, ref StrEmployee);
                        ComboEmployee.Text  = StrEmployee;
                        TxtTotalAmount.Text = decimalTotalAmount.ToString();
                        TxtPeriod.Text      = IntPeriod.ToString();
                        TxtReason.Text      = StrResason;
                        ComboStatus.Text    = StrStatues;
                        if (varSettlementDate != null)
                        {
                            DateSettlement.Value = varSettlementDate.Value;
                        }
                        TxtChequeNo.Text = StrChequeNo;
                        if (VarChequeDate != null)
                        {
                            DateChequeDate.Value = VarChequeDate.Value;
                        }
                        if (VarExpenseDate != null)
                        {
                            DateChequeExpense.Value = VarExpenseDate.Value;
                        }
                        if (VarExpenseDate != null)
                        {
                            DateChequeExpense.Value = VarExpenseDate.Value;
                        }
                        if (VarEndDate != null)
                        {
                            DateEndDate.Value = VarEndDate.Value;
                        }
                        TxtSettlementAmount.Text = decimalSettlementAmount.ToString();
                        TxtSettlementPeriod.Text = IntSettlementPEriod.ToString();
                        TxtTax.Text           = decimalTax.ToString();
                        TxtPenalty.Text       = decimalPenalty.ToString();
                        TxtFees.Text          = decimalFees.ToString();
                        TxtRevenues.Text      = decimalRevenues.ToString();
                        TxtNetAmount.Text     = decimalNetAmount.ToString();
                        TxtTotalDiscount.Text = decimalTotalDiscount.ToString();
                        TxtAmountToPay.Text   = decimalAmountToPay.ToString();
                        TxtPaidAmount.Text    = decimalPaidAmount.ToString();
                        TxtBill.Text          = StrBillNo;
                        TxtSettlementNo.Text  = StrSettlementNo;
                        TxtNotes.Text         = StrNotes;
                    }
                    else
                    {
                        DatePayDate.Value        = DateTime.Now;
                        ComboLocation.Text       = "";
                        ComboEmployee.Text       = "";
                        TxtTotalAmount.Text      = "";
                        TxtPeriod.Text           = "";
                        TxtReason.Text           = "";
                        ComboStatus.Text         = "";
                        DateSettlement.Value     = DateTime.Now;
                        TxtChequeNo.Text         = "";
                        DateChequeDate.Value     = DateTime.Now;
                        DateChequeExpense.Value  = DateTime.Now;
                        DateEndDate.Value        = DateTime.Now;
                        TxtSettlementAmount.Text = "";
                        TxtSettlementPeriod.Text = "";
                        TxtTax.Text           = "";
                        TxtPenalty.Text       = "";
                        TxtFees.Text          = "";
                        TxtRevenues.Text      = "";
                        TxtNetAmount.Text     = "";
                        TxtTotalDiscount.Text = "";
                        TxtAmountToPay.Text   = "";
                        TxtPaidAmount.Text    = "";
                        TxtBill.Text          = "";
                        TxtSettlementNo.Text  = "";
                        TxtNotes.Text         = "";
                    }
                }
            }
            catch (NullReferenceException)
            {
            }
            catch (InvalidOperationException)
            {
                DatePayDate.Value        = DateTime.Now;
                ComboLocation.Text       = "";
                ComboEmployee.Text       = "";
                TxtTotalAmount.Text      = "";
                TxtPeriod.Text           = "";
                TxtReason.Text           = "";
                ComboStatus.Text         = "";
                DateSettlement.Value     = DateTime.Now;
                TxtChequeNo.Text         = "";
                DateChequeDate.Value     = DateTime.Now;
                DateChequeExpense.Value  = DateTime.Now;
                DateEndDate.Value        = DateTime.Now;
                TxtSettlementAmount.Text = "";
                TxtSettlementPeriod.Text = "";
                TxtTax.Text           = "";
                TxtPenalty.Text       = "";
                TxtFees.Text          = "";
                TxtRevenues.Text      = "";
                TxtNetAmount.Text     = "";
                TxtTotalDiscount.Text = "";
                TxtAmountToPay.Text   = "";
                TxtPaidAmount.Text    = "";
                TxtBill.Text          = "";
                TxtSettlementNo.Text  = "";
                TxtNotes.Text         = "";
                BtnDelete.Enabled     = false;
            }
            catch (Exception EX)
            {
                MessageBox.Show(EX.Message.ToString());
            }
        }