private void frmProduct_Load(object sender, EventArgs e)
 {
     clearAll();
     selectClass.viewPatient(dataGridView2);
     selectClass.GetSuppliers(cboSuppliedBy);
     selectClass.GetSuppliers(cboUpSuppliedBy);
     selectClass.SelectDrugName(cboLoadDrug);
     textBox4.Text = "1";
 }