private void btnSave_Click(object sender, EventArgs e)
        {
            if (ValidateChildren(ValidationConstraints.Enabled))
            {
                try
                {
                    auto_generate_id();
                    BusinessManager BM = new BusinessManager();
                    BOCustomer      BO = new BOCustomer();
                    BO.CustomerID         = txtCustomerID.Text.Trim();
                    BO.CustomerName       = txtCustomerName.Text.Trim();
                    BO.CustomerAddress    = txtAddress.Text.Trim();
                    BO.CustomerPlace      = txtPlace.Text.Trim();
                    BO.CustomerCity       = txtCity.Text.Trim();
                    BO.CustomerZone       = cmbZone.Text.Trim();
                    BO.CustomerPostalCode = txtPostalCode.Text.Trim();
                    BO.CustomerPhone      = txtPhone.Text.Trim();
                    BO.CustomerMobile     = txtMobile.Text.Trim();
                    BO.CustomerFax        = txtFax.Text.Trim();
                    BO.CustomerEmail      = txtEmail.Text.Trim();
                    BO.CustomerNotes      = txtNote.Text.Trim();

                    bool res          = BM.BALVerifyCustomerName(BO);
                    int  rowsAffected = 0;
                    if (res == true)
                    {
                        MessageBox.Show("Customer ID already exists", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                        New();
                    }
                    else
                    {
                        rowsAffected = BM.BALInsertIntoCustomer(BO);
                        if (rowsAffected > 0)
                        {
                            MessageBox.Show("Successfully saved", "Success", MessageBoxButtons.OK, MessageBoxIcon.Information);
                            btnSave.Enabled = false;
                            New();
                        }
                    }
                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }
        }