private void btnCategoryDelete_Click(object sender, EventArgs e)
 {
     try
     {
         DialogResult d = MessageBox.Show("Are you sure you want to delete?", "Delete", MessageBoxButtons.YesNo);
         if (d == DialogResult.Yes)
         {
             StoreRepo.delete(this.id);
             List <SMLIB.Entity.Store> s = StoreRepo.retrieve();
             initStore(s);
             btnCategoryDelete.Enabled = false;
             btnCategoryUpdate.Enabled = false;
             btnCategoryAdd.Enabled    = true;
             MessageBox.Show("Store has been deleted.");
             clearAll();
         }
     }
     catch (Exception)
     {
         MessageBox.Show("Please select an item to delete.");
     }
 }