Question

我将向用户上传图片，并将其显示在模板中。

我安装了枕头，并添加了@property，但问题仍未解决。

my requirements.tct includes:
Django==2.2
django-crispy-forms==1.7.2
Pillow==6.0.0
pytz==2019.1
sqlparse==0.3.0

in models.py 
class Melk(models.Model):
    city = models.CharField(max_length=50)
    image =  models.ImageField(upload_to = 'pic_folder', blank = True)
    def __str__(self):
        return self.city

    @property
    def image_url(self):
        if self.image and hasattr(self.image, 'url'):
            return self.image.url



in template
    <div class="page-header">        
      {% if show_mine %}
        <ul>
          <div class="row">
              {% for show in show_mine %}
              <div class="col-lg-4 mb-4">
                  <li>
                      {{ show.image.url | default_if_none:'#' }}                        
                      {{ show.city }}  
                  </li>
              </div>
              {% endfor %}
          </div>
        </ul>     
      {% endif %}
    </div>

程序在没有图像字段的情况下可以正常运行。我希望用户可以在模板中看到他上传的图像。

错误是：

    ValueError at /users/home/
The 'image' attribute has no file associated with it.
Request Method: GET
Request URL:    http://127.0.0.1:8000/users/home/
Django Version: 2.2
Exception Type: ValueError
Exception Value:    
The 'image' attribute has no file associated with it.
Exception Location: C:\Users\Student\Desktop\myproject\lib\site-packages\django\db\models\fields\files.py in _require_file, line 38
Python Executable:  C:\Users\Student\Desktop\myproject\Scripts\python.exe
Python Version: 3.7.3

Answer 1

问题是由于没有文件链接到ImageField，因此将 {{show.image.url}} 置于if条件下，

{% if show.image %}
   {{ show.image.url }} 
{% endif %}

验证文件链接是否正常工作。您可以在ImageField中添加默认值，

avatar = models.ImageField(upload_to='avatars/', null=True, blank=True, default='/static/img/default-user.png')

或者您可以更改自定义属性，例如

@property
def image_url(self):
    if self.image:
        return self.image.url
    return '#'

ValueError-'image'属性没有与之关联的文件。模板渲染期间发生错误

1 个答案: