Ruby on rails Simple验证意外命名错误的长度

Ruby on rails Simple验证意外命名错误的长度,ruby-on-rails,validation,model,controller,Ruby On Rails,Validation,Model,Controller,我有一个消息表单,它在模型中使用validates_length_限制消息的长度 validates_length_of :content, :maximum => 1024 我通过输入5个左右的字符来“测试”这一点,并提交了表格。但我得到了这个命名法: NoMethodError in Messages#create Showing app/views/messages/_messages.html.erb where line #1 raised: You have a ni

我有一个消息表单,它在模型中使用validates_length_限制消息的长度

validates_length_of   :content, :maximum => 1024
我通过输入5个左右的字符来“测试”这一点,并提交了表格。但我得到了这个命名法:

NoMethodError in Messages#create

Showing app/views/messages/_messages.html.erb where line #1 raised:

You have a nil object when you didn't expect it!
You might have expected an instance of Array.
The error occurred while evaluating nil.each
Extracted source (around line #1):

1: <%- for message in @messages -%>
2:   <div class="message">
3:     <%= link_to message.title, message %>
....
消息#创建:

_messages.html.erb:(非常难看,需要进行重大重构)


通过
活跃的 ;
'messages',:action=>show',:id=>message%>
'messages',:action=>show',:id=>message%>
%w(嵌入img对象p参数),
:attributes=>%w(allowfullscreen allowscriptaccess href name src type value)%%>

message.firstcomments%> = 4 -%> '显示',:id=>message%>

我不确定这里到底发生了什么。任何帮助都将不胜感激(即使是部分重构)。感谢阅读我的问题。

您好,当您输入5k左右的字符时,
消息
将成为无效记录,因此请创建已工作的
否则
条件

else
  format.html { render :action => "index" }
end
您在这里渲染
render
不会在操作中执行代码,它只是在
创建
操作(我想您也没有在
new
中执行该操作)中使用您未分配的
@messages
当前数据渲染文本文件,因此在渲染
索引时它是
nil

您应该在
new
create
中初始化它,或将
render'index'
更改为
render'new'

您在哪里声明@messages变量?那就是引起争议的那个nil@messages在消息#索引中。我更新了这个问题以显示代码。谢谢,我不知道为什么它被改为索引。
def create
  @message = Message.new(params[:message])
  respond_to do |format|
    if @message.save
      record_post_time
      flash[:notice] = "Created \"#{@message.title}\""
      format.html { redirect_to(messages_url) }
    else
      format.html { render :action => "index" }
    end
  end
end
<%- for message in @messages -%>
  <div class="message">
    <%= link_to message.title, message %>

    <%- if message.name.empty? -%>

    <%- else -%>   
      <span class="name">
        by 
        <%- if message.email.blank? -%>
          <%=h message.name %>
        <%- else -%>
          <a href="mailto:<%= message.email %>"><%=h message.name %></a>
        <%- end -%>
      </span>
    <%- end -%>

    <span class="time">
      active &#32;<%= timeago(message.updated_at) %>
    </span>

    <%- if message.comments.empty? -%>
      <span class="reply">
        <%= link_to 'reply', :controller => 'messages', :action => 'show', :id => message %>
      </span>
    <% else %>
      <span class="reply">
        <%= link_to pluralize(message.comments.count, 'reply'), :controller => 'messages', :action => 'show', :id => message %>
      </span>
    <%- end -%>

    <p><%= sanitize message.content,
 :tags => %w(a embed img object p param),
 :attributes => %w(allowfullscreen allowscriptaccess href name src type value) %></p>

    <% unless controller.controller_name == "tags" %>
      <%- unless message.tag_list.nil? || message.tag_list.empty? -%>
        <% message.tags.each do |t| %>
          <div class="tag"><%= link_to t.name.titleize, tag_path(t) %></div>
        <% end %>
      <%- end -%>
    <% end %>

    <%- unless message.comments.empty? -%>
      <div class="comments">
        <%= render :partial => message.firstcomments %>
        <%- if message.comments.count >= 4 -%>
          <%= link_to 'more...', :action => 'show', :id => message %>
        <%- end -%>
      </div>
    <%- end -%>
  </div>
<%- end -%>
else
  format.html { render :action => "index" }
end