Rails表单验证 #

class Article < ApplicationRecord
  validates :title, presence: true, length: { minimum: 5 }
  validates :body, presence: true
end

def create
  @article = Article.new(article_params)
  
  if @article.save
    redirect_to @article, notice: '创建成功'
  else
    render :new, status: :unprocessable_entity
  end
end

<% if @article.errors.any? %>
  <div class="alert alert-danger">
    <h4><%= pluralize(@article.errors.count, 'error') %></h4>
    <ul>
      <% @article.errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
    </ul>
  </div>
<% end %>