private void btnedit_Click(object sender, EventArgs e)
 {
     db = new db_MiletecDataContext();
     if (txtSupplierName.Text != "Supplier Name" && txtAddress.Text != "Address" && txtContact1.Text != "Contact No.1" && txtContact2.Text != "Contact No.2" &&
         txtContactPerson.Text != "Contact Person")
     {
         db.sp_Update_SupplierDetails(txtSupplierID.Text, txtSupplierName.Text, txtAddress.Text,
                                      int.Parse(txtContact1.Text), int.Parse(txtContact2.Text), txtContactPerson.Text);
         db.SubmitChanges();
         MessageBox.Show("Successfuly Updated.", "NOTE", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);
         Display();
         txtSupplierName.Text  = "Supplier Name";
         txtAddress.Text       = "Address";
         txtContact1.Text      = "Contact No.1";
         txtContact2.Text      = "Contact No.2";
         txtContactPerson.Text = "Contact Person";
     }
     else
     {
         MessageBox.Show("Please fill up everything first.", "NOTE", MessageBoxButtons.OK, MessageBoxIcon.Error);
     }
 }