spitfire_tree https://blog.hatena.ne.jp/spitfire_tree/ happy lie, happy life https://spitfire-tree.hatenadiary.org/ Rails コード def if_found(obj, msg = "デフォルトのエラーメッセージ", action = "index", controller = controller_name) if obj yield if block_given? else flash[:error] = msg redirect_to :controller => controller, :action => action end end 使い方 まずは action_controller に上のメソッドを記述します。実際の利用方法は以下のとおり。 if_found(@item = Item.find(para… 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Fspitfire-tree.hatenadiary.org%2Fentry%2F20080809%2F1218269418" title="if_found メソッドを本格的に考えてみる - happy lie, happy life" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> https://thumbnail.image.rakuten.co.jp/@0_mall/book/cabinet/3531/9784873113531.jpg?_ex=128x128 Hatena Blog https://hatena.blog 2008-08-09 17:10:18 rich https://spitfire-tree.hatenadiary.org/entry/20080809/1218269418 1.0 100%