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Python 在django中创建缩略图时出现问题_Python_Django - Fatal编程技术网

Python 在django中创建缩略图时出现问题

Python 在django中创建缩略图时出现问题,python,django,Python,Django,代码如下: class Document(models.Model): docfile = models.FileField(upload_to='documents/big/') thumbnail = models.FileField(upload_to='documents/small/') def create_thumbnail(self): if not self.image: return

代码如下:

class Document(models.Model):
    docfile = models.FileField(upload_to='documents/big/')
    thumbnail = models.FileField(upload_to='documents/small/')

    def create_thumbnail(self):        
        if not self.image:
            return         

        from PIL import Image
        from cStringIO import StringIO
        from django.core.files.uploadedfile import SimpleUploadedFile
        import os


        THUMBNAIL_SIZE = (200,200)

        DJANGO_TYPE = self.image.file.content_type

        if DJANGO_TYPE == 'image/jpeg':
            PIL_TYPE = 'jpeg'
            FILE_EXTENSION = 'jpg'

        elif DJANGO_TYPE == 'image/png':
            PIL_TYPE = 'png'
            FILE_EXTENSION = 'png'


        image = Image.open(StringIO(self.image.read()))


        image.thumbnail(THUMBNAIL_SIZE, Image.ANTIALIAS)


        temp_handle = StringIO()
        image.save(temp_handle, PIL_TYPE)
        temp_handle.seek(0)


        suf = SimpleUploadedFile(os.path.split(self.image.name)[-1],
         temp_handle.read(), content_type=DJANGO_TYPE)

        self.thumbnail.save('%s_thumbnail.%s'%(os.path.splitext(suf.name)[0],FILE_EXTENSION), suf, save=False)

        def save(self):         

           self.create_thumbnail()
           super(ImageWithThumbnail, self).save()

现在我想将缩略图保存在
documents/small/
中。但是,在上载图像以创建缩略图时,如何从视图或模型调用该函数?

您的意思是要在视图中调用该函数吗。 那你就可以了

from urappname.models import Document
并使用

Document.create_thumbnail()

可以通过重写django的默认save()方法来实现这一点。 为此,请在模型类下定义此save()函数,如下所示:

def save(self, *args, **kwargs):
    self.create_thumbnail()
    super(Document, self).save(*args, **kwargs)

实际上,我想在上传图像时动态创建缩略图。在我的查看页面中,我将数据保存在数据库中,如下所示:newdoc=Document(docfile=request.FILES['docfile'],缩略图=request.FILES['docfile'])newdoc.save()