这是views.py中的代码
def store (request):
products = {
'products':product.objects.all()
}
return render (request, 'neizer/products.html', context = products)
这是模板
{% block content %}
<div class="products-parent">
{%for product in products%}
<div class="product-child">
<img src={{product.image.url}} alt="no image available" />
<h2>{{product.name}}</h2>
<button id="learn-more-btn">learn more</button>
<p>${{product.price}} <i class="fas fa-cart-plus"></i></p>
</div>
{% endfor %}
</div>
{% endblock content %}
我使用/ admin界面上传图像,当我在django shell中访问图像url时,我得到一个实际的url(在浏览器中打开到该图像),但是当我尝试在模板中访问它时,我得到了以上错误,product.image.url
似乎是问题所在,但django似乎并没有使类实例正确。这是回溯:
Traceback (most recent call last):
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 828, in _resolve_lookup
current = current[bit]
During handling of the above exception ('ImageFieldFile' object is not subscriptable), another exception occurred:
File "/mnt/s/env/lib/python3.6/site-packages/django/core/handlers/exception.py", line 34, in inner
response = get_response(request)
File "/mnt/s/env/lib/python3.6/site-packages/django/core/handlers/base.py", line 115, in _get_response
response = self.process_exception_by_middleware(e, request)
File "/mnt/s/env/lib/python3.6/site-packages/django/core/handlers/base.py", line 113, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/mnt/s/webapp/main/views.py", line 20, in store
return render (request, 'neizer/products.html', context = products)
File "/mnt/s/env/lib/python3.6/site-packages/django/shortcuts.py", line 19, in render
content = loader.render_to_string(template_name, context, request, using=using)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/loader.py", line 62, in render_to_string
return template.render(context, request)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/backends/django.py", line 61, in render
return self.template.render(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 171, in render
return self._render(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 163, in _render
return self.nodelist.render(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 936, in render
bit = node.render_annotated(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 903, in render_annotated
return self.render(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/loader_tags.py", line 150, in render
return compiled_parent._render(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 163, in _render
return self.nodelist.render(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 936, in render
bit = node.render_annotated(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 903, in render_annotated
return self.render(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/loader_tags.py", line 62, in render
result = block.nodelist.render(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 936, in render
bit = node.render_annotated(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 903, in render_annotated
return self.render(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/defaulttags.py", line 209, in render
nodelist.append(node.render_annotated(context))
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 903, in render_annotated
return self.render(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 986, in render
output = self.filter_expression.resolve(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 670, in resolve
obj = self.var.resolve(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 795, in resolve
value = self._resolve_lookup(context)
File "/mnt/s/env/lib/python3.6/site-packages/django/template/base.py", line 836, in _resolve_lookup
current = getattr(current, bit)
File "/mnt/s/env/lib/python3.6/site-packages/django/db/models/fields/files.py", line 61, in url
self._require_file()
File "/mnt/s/env/lib/python3.6/site-packages/django/db/models/fields/files.py", line 38, in _require_file
raise ValueError("The '%s' attribute has no file associated with it." % self.field.name)
Exception Type: ValueError at /store
Exception Value: The 'image' attribute has no file associated with it.
{% if person.image %}
<img src={{product.image.url}} />
{% else %}
<img src="#" alt="no image available" />
{% endif %}
另一种方法是为图像字段(默认图像)设置一个默认值:
image = models.ImageField(upload_to='whatever', default='your_default_image.jpg')
或至少在模板中放入默认图像:
...
{% else %}
<img src="{% static 'your_default_img_path' %}" >
...
还有另一种方法是为模型的用户属性:
@property
def get_image_url(self):
if self.image and hasattr(self.image, 'url'):
return self.image.url
else:
return "/static/images/your_default_image.jpg"