private void comNameComboBox_SelectedIndexChanged(object sender, EventArgs e)
 {
     try
     {
         ComboBox cmb           = (ComboBox)sender;
         int      selectedIndex = cmb.SelectedIndex;
         int      selectedValue = (int)cmb.SelectedValue;
         string   comId         = String.Format("{0}", selectedValue);
         stockinModel.ComId = Convert.ToInt32(comId);
         _stockInManagers.CatWiseItems(stockinModel);
         catNameComboBox.DataSource    = _stockInManagers.ComWiseCat(stockinModel);
         catNameComboBox.DisplayMember = "Name";
         catNameComboBox.ValueMember   = "Id";
     }
     catch (Exception ex)
     {
         MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
     }
 }