在django中向用户添加图片/头像字段

#models.py
from django.contrib.auth.models import User

class UserProfile(models.Model):
    user   = models.OneToOneField(User)
    avatar = models.ImageField()


#forms.py
from django import forms
from django.core.files.images import get_image_dimensions

from my_app.models import UserProfile


class UserProfileForm(forms.ModelForm):
    class Meta:
        model = UserProfile

    def clean_avatar(self):
        avatar = self.cleaned_data[\'avatar\']

        try:
            w, h = get_image_dimensions(avatar)

            #validate dimensions
            max_width = max_height = 100
            if w > max_width or h > max_height:
                raise forms.ValidationError(
                    u\'Please use an image that is \'
                     \'%s x %s pixels or smaller.\' % (max_width, max_height))

            #validate content type
            main, sub = avatar.content_type.split(\'/\')
            if not (main == \'image\' and sub in [\'jpeg\', \'pjpeg\', \'gif\', \'png\']):
                raise forms.ValidationError(u\'Please use a JPEG, \'
                    \'GIF or PNG image.\')

            #validate file size
            if len(avatar) > (20 * 1024):
                raise forms.ValidationError(
                    u\'Avatar file size may not exceed 20k.\')

        except AttributeError:
            \"\"\"
            Handles case when we are updating the user profile
            and do not supply a new avatar
            \"\"\"
            pass

        return avatar

#upload at specific location
avatar = models.ImageField(upload_to=\'images\')

<img src=path/to/images/{{ user.get_profile.avatar }}\">

contrib.auth

AUTH_PROFILE_MODULE

from django.contrib.auth.models import User

class UserProfile(models.Model):
    user   = models.OneToOneField(User)
    avatar = models.ImageField() # or whatever