django前端渲染多对多关系（比如一本书的作者有哪些）

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自己遇到的问题是，前端渲染不出多对多关系，咨询Yuan后解决，特此记录。

urls.py

from django.conf.urls import url
from book import viewsurlpatterns = [
url(r'^index/', views.index),
url(r'^add/', views.add),
url(r'^delete/', views.delete),
url(r'^modify/', views.modify),
]

models.py

from django.db import models# Create your models here.class Publisher(models.Model):
name = models.CharField(max_length=, verbose_name="名称")
address = models.CharField("地址", max_length=)
city = models.CharField('城市', max_length=)
state_province = models.CharField(max_length=)
country = models.CharField(max_length=)
website = models.URLField() class Meta:
verbose_name = '出版商'
verbose_name_plural = verbose_name def __str__(self):
return self.nameclass Author(models.Model):
name = models.CharField(max_length=) def __str__(self):
return self.nameclass AuthorDetail(models.Model):
# sex = models.BooleanField(max_length=, choices=((, '男'), (, '女'),))
sex = models.CharField(max_length=)
email = models.EmailField()
address = models.CharField(max_length=)
birthday = models.DateField()
author = models.OneToOneField(Author) def __str__(self):
return '(%s,%s,%s)' % (self.sex, self.email, self.address)class Book(models.Model):
title = models.CharField(max_length=)
price = models.DecimalField(max_digits=, decimal_places=, default=)
authors = models.ManyToManyField('Author')
publisher = models.ForeignKey('Publisher')
publication_date = models.DateField(default='2017-08-20') def __str__(self):
return self.title

views.py

def index(request):
all_book_list = Book.objects.all() # 获取所有book对象
if request.method == "POST": # 搜索框的POST请求和数据
key_word = request.POST.get('key_word')
all_book_list = Book.objects.filter(title__contains=key_word)
return render(request, "book/index.html", {"all_book_list": all_book_list})

book/book.index.html

{% load staticfiles %}<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>内部管理系统</title>
<link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://cdn.bootcss.com/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<style>
ul{
padding: 20px 30px 20px 50px;
}
ul li {
margin: 30px ;
}
{# 分割 #}
.outer{
margin: 100px auto;
width: %;
height: 400px;
border: 1px solid rebeccapurple;
position: relative;
}
.search_form {
position: absolute;
top: 10px;
left: 750px;
}
.table-content {
position: absolute;
top: 50px;
}
.form {
display: inline-block;
}
.add-button{
position: absolute;
right: 20px;
bottom: 20px;
}
</style>
<link rel="stylesheet" href="{% static "dist/css/bootstrap.css" %}">
</head>
<body>
<ul id="myTab" class="nav nav-tabs">
<li class="active">
<a href="#book" data-toggle="tab">书籍管理</a>
</li>
<li>
<a href="/author/index">作者管理</a>
</li>
<li>
<a href="/publisher/index">出版社管理</a>
</li>
<li class="dropdown">
<a href="#" id="myTabDrop1" class="dropdown-toggle"
data-toggle="dropdown">学科<b class="caret"></b>
</a>
<ul class="dropdown-menu" role="menu" aria-labelledby="myTabDrop1">
<li><a href="#yuwen" tabindex="-1" data-toggle="tab">
语文</a>
</li>
<li><a href="#shuxue" tabindex="-1" data-toggle="tab">
数学</a>
</li>
</ul>
</li>
</ul>
<div id="myTabContent" class="tab-content">
<div class="tab-pane fade in active" id="book">
<div class="outer">
<form class="col-lg-2 input-group search_form" action="/index/" method="post">
<input class="form-control form" placeholder="Search for..." type="text" name="key_word">

<span class="input-group-btn">
<input class="btn btn-default" type="submit">Go2!</input>
</span>
</form>
<table class="table table-striped table-content">
<tbody>
<tr>
<th>编号</th>
<th>书名</th>
<th>价格</th>
<th>作者</th>
<th>出版社</th>
<th>出版日期</th>
<th>         action</th>
</tr>
{% for book in all_book_list %}
<tr>
<td>{{ book.id }}</td>
<td>{{ book.title }}</td>
<td>{{ book.price }}</td>
<td>{{ book.authors }}</td> //这块是问题点
<td>{{ book.publisher }}</td>
<td>{{ book.publication_date|date:'Y-m-d'}}</td>
<td>
<a href="/book/delete/?id={{ book.id }}"><button type="button" class="btn btn-danger">删除</button></a>

<button type="button" class="btn btn-primary modify" data-toggle="modal" data-target="#myModal">编辑</button>
</td>
</tr>
{% endfor %}
</tbody> </table>
<a href="/book/add/"><button type="button" class="btn btn-primary add-button">添加</button></a>
</div>

<div class="modal fade" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel">
<div class="modal-dialog" role="document">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">×</span></button>
<h4 class="modal-title" id="myModalLabel">编辑模式</h4>
</div>
<form action="/book/modify/" method="post">
<div class="modal-body">
<div class="input-group">
<span class="input-group-addon" id="basic-addon1">ID</span>
<input type="text" class="form-control BookId" aria-describedby="basic-addon1" name="BookId">
</div>
<div class="input-group">
<span class="input-group-addon" id="basic-addon1">书名</span>
<input type="text" class="form-control BookName" aria-describedby="basic-addon1" name="BookName">
</div>
<div class="input-group">
<span class="input-group-addon" id="basic-addon1">价格</span>
<input type="text" class="form-control Price" aria-describedby="basic-addon1" name="Price">
</div>
<div class="input-group">
<span class="input-group-addon" id="basic-addon1">作者</span>
<input type="text" class="form-control Author" aria-describedby="basic-addon1" name="Author">
</div>
<div class="input-group">
<span class="input-group-addon" id="basic-addon1">出版社</span>
<input type="text" class="form-control Publisher" aria-describedby="basic-addon1" name="Publisher">
</div>
<div class="input-group">
<span class="input-group-addon" id="basic-addon1">出版日期</span>
<input type="text" class="form-control Publication_date" aria-describedby="basic-addon1" name="Publication_date">
</div>
</div>
<div class="modal-footer">
<button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
<button type="submit" class="btn btn-primary" id="modify_confirm">Save changes</button>
</div>
</form>
</div>
</div>
</div>
</div>
<div class="tab-pane fade" id="author">
</div>
<div class="tab-pane fade" id="publisher">
</div>
<div class="tab-pane fade" id="jmeter">
<p>语文。。。。</p>
</div>
<div class="tab-pane fade" id="ejb">
<p>数学。。。。。</p>
</div>
</div>

<script src="{% static "dist/js/BookManagerSystem_book.js" %}"></script>
</body>
</html>

在前端模板语言中，如上方式使用

<td>{{ book.authors }}</td>

结果：

使用

<td>{{ book.authors.all }}</td>

结果

使用：

{% for book_author in {{ book.authors.all }} %}
<td>{{ book_author }}</td>
{% endfor %}

效果

使用：

{% for book_author in book.authors.all %}
<td>{{ book_author }}</td>
{% endfor %}

效果

正确的做法：

{% for book in all_book_list %}
<tr>
<td>{{ book.id }}</td>
<td>{{ book.title }}</td>
<td>{{ book.price }}</td>
<td>
{% for book_author in book.authors.all %}
{{ book_author }}
{% endfor %}
</td> //将循环放在td标签内
<td>{{ book.publisher }}</td>
<td>{{ book.publication_date|date:'Y-m-d'}}</td>
<td>
<a href="/book/delete/?id={{ book.id }}"><button type="button" class="btn btn-danger">删除</button></a>

<button type="button" class="btn btn-primary modify" data-toggle="modal" data-target="#myModal">编辑</button>
</td>
</tr>
{% endfor %}