private void Cash_Payment_Click(object sender, EventArgs e)
        {
            int warning = 0;

            amount = Cash_Amount_TB.Text;
            bool allDigitCSH = amount.All(char.IsDigit);

            if (amount == "")
            {
                MessageBox.Show("Please Enter the Amount");
            }
            else
            {
                if (allDigitCSH == false)
                {
                    MessageBox.Show("Invalid Amount!!!");
                    warning = 3;
                }
                else
                {
                    payment = Convert.ToInt32(amount);
                }
                if (warning == 0)
                {
                    if (payment >= totalAmount)
                    {
                        int cusID = Convert.ToInt32(cID);
                        //string path=Path.GetRandomFileName();
                        //path=path.Replace(".","");
                        //cCount++;
                        string        path = "12345" + cName;
                        Customer_Info ciT  = new Customer_Info
                        {
                            CID          = cusID,
                            CName        = cName,
                            CGender      = cGender,
                            CDOB         = cDOB,
                            CPhone_Num   = cPN,
                            CEmail       = cEID,
                            CPassport_No = cPPNo,
                            CNationality = cNationality,
                            //Card_Holder_Name=cHName,
                            //Credit_Card_No=Convert.ToInt32(cCNo),
                            //Card_Expire_Date=cCEd,
                            CPassword = path
                        };

                        cpD.Customer_Infos.InsertOnSubmit(ciT);
                        cpD.SubmitChanges();

                        var x = from a in cpD.Flight_Details
                                where a.Flight_ID == flightListNo
                                select a;

                        string fN = x.First().Flight_Name;
                        x.First().Available_Seat_E_ = sEAvail;
                        x.First().Available_Seat_B_ = sBAvail;

                        cpD.SubmitChanges();


                        var y = from b in cpD.Flight_Details
                                //where a.Flight_Name == APSearchBox.Text
                                where b.Available_Seat_B_ == 0 &&
                                b.Available_Seat_E_ == 0
                                select b;

                        foreach (Flight_Detail p in y)
                        {
                            cpD.Flight_Details.DeleteOnSubmit(p);
                        }

                        cpD.SubmitChanges();


                        TicketBooked_Info tbT = new TicketBooked_Info
                        {
                            CID                 = cusID,
                            CName               = cName,
                            Flight_ID           = flightListNo,
                            Flight_Name         = fN,
                            Business_Seat_Taken = intoB,
                            Economy_Seat_Taken  = intoE
                        };

                        cpD.TicketBooked_Infos.InsertOnSubmit(tbT);
                        cpD.SubmitChanges();

                        if (payment > totalAmount)
                        {
                            payment = payment - totalAmount;
                            MessageBox.Show("Your return back amount is : " + payment + " BDT");
                        }

                        MessageBox.Show("Ticket Confirmation is Successfull!! :)\n\nYour User Password is : " + path + "\n\nyou can login with your user name using this password from login panel! ");
                        this.Hide();
                        AIRRMainFrame mF = new AIRRMainFrame();
                        mF.Show();
                    }
                    else if (payment < totalAmount)
                    {
                        MessageBox.Show("Your amount is Insufficient!!");
                    }
                }
            }
        }