ruby-on-rails – Rails：在表单提交后访问视图中的参数

<%= form_for(@site) do |site_form| %>
  ...
  <div class="field">
    <%= site_form.label :hash_name %><br />
    <%= site_form.text_field :hash_name %>
  </div>
  ...
  <div class="actions">
    <%= site_form.submit %>
  </div>
<% end %>

然后是sites_controller.rb中的create函数

def create
  @site = Site.new(params[:site])

  respond_to do |format|
    if @site.save
      format.html { redirect_to @site }
    else
      format.html { render action: "new" }
    end
  end
end

然后在用户提交后,我想在show.html.erb中显示用户刚刚提交的hash_name

You just put in <%= params[:hash_name] %>.

但访问params [：hash_name]不起作用.我该如何访问它？