private void AssignTaskMaterialsMaterialNameTextBox_TextChanged(object sender, RoutedEventArgs e) { try { // get the quantity of materials DB1 = new DBManager(); this.AssignTaskMaterialsStockQuantityTextBlock.Text = DB1.GetStock("SELECT b.* , a.material_name FROM materials a , stock_materials b WHERE a.material_id = b.material_id AND a.material_name = '" + this.AssignTaskMaterialsMaterialNameTextBox.Text + "'").First().quanitity.ToString(); } catch { } }