private void btnPlumSubAdd_Click(object sender, EventArgs e)
 {
     Form frmContractorAdd = new ContractorAdd();
     frmContractorAdd.Show();
 }
 private void btnContractorAdd_Click(object sender, EventArgs e)
 {
     Form frmContractorAdd = new ContractorAdd();
     cmboConstructionType.SelectedIndex = 0;
     frmContractorAdd.Show();
 }