django - How to insert the content of uploaded file in template?

Question

Say I've stored a text file in FileField. Now I want to display its content on the webpage. I read the django template document but didn't find a way to do this.

Of course I can do content = f.read() in my views and pass content to the template. Is there a better way? Thank you!

better way means I could get the job done by passing MyModel.objects.all() to template.I can't read a file in template, but there should be some kind of hacks for this.

edit
I've tried:

def display_html(self):
    content = self.html_file.read()
    print(content)
    return content

but nothing displayed...

final edit
It's very strange that the following code works

class MyModel(models.Model):
    name = models.CharField()
    text = models.FileField()

    def display_text_file(self):
        fp = open(self.text.path)
        return fp.read().replace('\n', '<br>')

However what I regard as equivalent doesn't work:

class MyModel(models.Model):
    name = models.CharField()
    text = models.FileField()

    def display_text_file(self):
        return self.text.read().replace('\n', '<br>')
        # neither do self.text.read().decode().replace('\n', '<br>')

I really want to know the reason.

Answer 1

You can define a method for your class that have FileField, if you want to do more than read method of FileField do, for for example display_text_file, and then in template call it.

Models:

class MyModel(models.Model):
    name = models.CharField(max_length=100)
    text = models.FileField(max_length=100, upload_to='.')

def display_text_file(self):
    with open(self.text.path) as fp:
        return fp.read().replace('\n', '<br>')

Views:

def show_files(request):
    objects = MyModel.objects.all()
    return render_to_response('show_files.html', {'objects': objects},
                              context_instance=RequestContext(request))

Templates:

{% for obj in objects %}

 <p>
   file name: {{obj.name}} <br>
   file content: {{obj.display_text_file}}
 </p>

{% endfor %}

For ways of opening file, in display_text_file, all of these ways works for me:

def display_text_file(self):
    with open(self.text.path) as fp:
        return fp.read().replace('\n', '<br>')

def display_text_file(self):
    self.text.open() # reset the pointer of file, needs if you need to read file more than once, in a request.
    return self.text.read().replace('\n', '<br>')

def display_text_file(self):
    self.text.open() # reset the pointer of file, needs if you need to read file more than once, in a request.
    return self.text.file.read().replace('\n', '<br>')

Type of self.text is django.db.models.fields.files.FieldFile and having following methods:

['DEFAULT_CHUNK_SIZE', 'chunks', 'close', 'closed', 'delete', 'encoding', 'field', 'file', 
'fileno', 'flush', 'instance', 'isatty', 'multiple_chunks', 'name', 'newlines', 'open', 'path', 
'read', 'readinto', 'readline', 'readlines', 'save', 'seek', 'size', 'softspace', 'storage', 'tell', 
'truncate', 'url', 'write', 'writelines', 'xreadlines']

And type of self.text.file is django.core.files.base.File and having following methods:

['DEFAULT_CHUNK_SIZE', 'chunks', 'close', 'closed', 'encoding', 'file', 
'fileno', 'flush', 'isatty', 'mode', 'multiple_chunks', 'name', 'newlines', 'open', 
'read', 'readinto', 'readline', 'readlines', 'seek', 'size', 'softspace', 'tell', 
'truncate', 'write', 'writelines', 'xreadlines']

And both of them have read method.