private void buttonSearchChild_Click(object sender, RoutedEventArgs e) { try { if (checkBoxChildByMom.IsChecked == true) { childList = bl.getKids(a => a.idMom == (long)comboBoxChildByMom.SelectedValue); } else { childList = bl.getKids(); } if (checkBoxNotNanny.IsChecked == true) { childList = from a in childList let x = a.idChild from b in bl.getAllChildWithoutNanny() where x == b.idChild select a; } if (checkBoxWithSpaiclNeed.IsChecked == true) { childList = from a in childList let x = a.idChild from b in bl.getKids(b => b.isSpecialNeed == true) where x == b.idChild select a; } dataGridDetailsChild.ItemsSource = childList; } catch (Exception Ex) { MessageBox.Show(Ex.Message); } }