从ManyToManyField中列出对象 [英] listing objects from ManyToManyField

问题描述

在我的模板中，我有：

  {％if meetings％} 
< ul> 
 {％会议中的会议％} 
< li> {{conference.date}}< / li> 
 {％for conference.speakers％} 
< li> {{conference.speakers}}< / li> 
 {％endfor％} 
 {％endfor％} 
< / ul> 
 {％else％} 
< p>否会议< / p> 
 {％endif％} 
  

在我的views.py文件中我有：

  from django.shortcuts import render_to_response 
 from youthconf.conference.models import会议
 
 def manageconf请求）：
 conference = Conference.objects.all（）。order_by（' -  date'）[：5] 
 return render_to_response（'conference / manageconf.html'，{'meetings'：meetings} ）
  

有一个名为会议的模型。其中有一个名为会议的类，名为演讲者

我得到错误：

 呈现时捕获异常：'ManyRelatedManager'对象不可迭代
  

此行： {％for conference.speakers％}

解决方案

您需要在多对多字段上调用 all 来获取一个迭代目的。另外，下一行应该包含说话者，而不是 conference.speakers 。

  {％for conference.speakers.all％} 
< li> {{speaker}}< / li> 
 {％endfor％} 
  

I am trying to print a list of all the Conferences and for each conference, print its 3 Speakers.

In my template I have:

{% if conferences %}
        <ul>
        {% for conference in conferences %}
                <li>{{ conference.date }}</li>
                {% for speakers in conference.speakers %}
                        <li>{{ conference.speakers }}</li>
                {% endfor %}
        {% endfor %}
        </ul>
{% else %}
<p>No Conferences</p>
{% endif %}

in my views.py file I have:

from django.shortcuts import render_to_response
from youthconf.conference.models import Conference

def manageconf(request):
        conferences = Conference.objects.all().order_by('-date')[:5]
        return render_to_response('conference/manageconf.html', {'conferences': conferences})

there is a model named conference. which has a class named Conferences with a ManyToManyField named speakers

I get the error:

Caught an exception while rendering: 'ManyRelatedManager' object is not iterable

with this line: {% for speakers in conference.speakers %}

解决方案

You need to call all on the many-to-many field to get an iterable object. Also, the next line should contain the speaker rather than conference.speakers.

{% for speaker in conference.speakers.all %}
        <li>{{ speaker }}</li>
{% endfor %}

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