修改controller,把循环放在create方法,

def create                                                                          
    @my_blog = MyBlog.new                                                             
      i = 1                                                                           
    loop do                                                                           
      if i > params[:mount].to_i                                                      
        break                                                                         
      end                                                                             
      @my_blog = MyBlog.create! title: params[:title], content: "#{(('A'..'Z').to_a + (0..9).to_a).shuffle[0,12].join}", created_at: Time.now, updated_at: Time.now
      i = i +1                                                                        
    end                                                                               
                                                                                      
    if @my_blog.save                                                                  
      redirect_to my_blogs_url, notice: '操作成功'                                    
    else                                                                              
      render :new                                                                     
    end                                                                               
  end   

把form表单数据进行改进,使用post,返回index页面

<%= link_to '返回', my_blogs_path %>
<%= form_tag '/my_blogs', method: :post do %>
  <label class="control-label">
    标题
    <i data-toggle="popover" data-togger="hover" data-container='body' data-html='true' title='说明:根据标题内关键词模糊查询' data-content='输入xxxxx' %>
    <%= text_field_tag :title, params[:title] %>
  </label>
    数量: <%= text_field_tag :mount, params[:mount], value: 1 %>
  <%= submit_tag '新建', class: "form_submit", class: 'btn btn-secondary btn-sm fa-input' %>
<% end %>