protected void ButtonAddCategory_Click(object sender, EventArgs e) { if (!CanAddCategory()) { ErrorSuccessNotifier.AddWarningMessage("Only admins can add categories"); return; } var context = new ApplicationDbContext(); string newCatName = this.TextBoxNewCategory.Text; if (string.IsNullOrWhiteSpace(newCatName)) { ErrorSuccessNotifier.AddErrorMessage("Please enter category name"); return; } else if (context.Categories.FirstOrDefault(c => c.Name == newCatName) != null) { ErrorSuccessNotifier.AddErrorMessage("Category with this name already exist"); return; } else { Models.Category cat = new Models.Category() { Name = newCatName }; context.Categories.Add(cat); context.SaveChanges(); this.TextBoxNewCategory.Text = ""; this.DataBind(); ErrorSuccessNotifier.AddSuccessMessage("Category added"); } }