Question

我需要获取具有相关图像的相册。我在第一循环 abc 和 abc123 中有两个相册，在abc相册中有两个图像，在abc123相册中有3个图像，但是我的回应是每张专辑返回5张图片。我无法建立适当的回应。

models.py

class Upload(models.Model):
    image=models.ImageField(upload_to='upload/', blank=True, null=True)
    user = models.ForeignKey(User, on_delete=models.CASCADE)
    # url= models.CharField(max_length=500)
    def __str__(self):
        return str(self.id)

class Album(models.Model):
    name = models.CharField(max_length=128)
    user = models.ForeignKey(User, on_delete=models.CASCADE)
    def __str__(self):
        return str(self.name)

class AlbumImage(models.Model):
    album = models.ForeignKey(Album, on_delete=models.CASCADE)
    image = models.ForeignKey(Upload, on_delete=models.CASCADE)

views.py

def getalbum(self,request):
    albums=Album.objects.filter(user=request.user)
    album={}
    image_list={}
    all_results=[]
    all_images=[]
    for a in albums:
        album_images=AlbumImage.objects.filter(album=a)
        for i in album_images:
            image_object=Upload.objects.get(id=str(i.image))
            image_list=str(image_object.image)
            all_images.append(image_list)
        album[a.name]=all_images
    all_results.append(album)
    return Response(all_results)

响应

[
    {
        "abc": [
            "upload/images_aPWBEcp.jpeg",
            "upload/images.jpeg",
            "upload/ic_id_card_placeholder_N0x2KP9.png",
            "upload/images_jocZcBu.jpeg",
            "upload/ic_id_card_placeholder_N0x2KP9.png"
        ],
        "abc123": [
            "upload/images_aPWBEcp.jpeg",
            "upload/images.jpeg",
            "upload/ic_id_card_placeholder_N0x2KP9.png",
            "upload/images_jocZcBu.jpeg",
            "upload/ic_id_card_placeholder_N0x2KP9.png"
        ]
    }
]

abc 相册

upload / images_aPWBEcp.jpeg

upload / images.jpeg

abc123 相册

upload / ic_id_card_placeholder_N0x2KP9.png

upload / images_jocZcBu.jpeg

upload / ic_id_card_placeholder_N0x2KP9.png

Answer 1

这里：

all_images=[]
for a in albums:
    album_images=AlbumImage.objects.filter(album=a)
    for i in album_images:
        image_object=Upload.objects.get(id=str(i.image))
        image_list=str(image_object.image)
        all_images.append(image_list)
    album[a.name]=all_images

您要在for循环之前初始化all_images并继续附加到该循环，因此两个相册最终都共享相同的图像列表。修复很容易：在for循环中初始化all_images：

for a in albums:
    all_images=[]
    album_images=AlbumImage.objects.filter(album=a)
    for i in album_images:
        image_object=Upload.objects.get(id=str(i.image))
        image_list=str(image_object.image)
        all_images.append(image_list)
    album[a.name]=all_images

话虽这么说，您正在使它变得比必须的复杂得多，并且您没有正确使用django的功能。不用手动创建AlbumImage模型，而是使用you could use a M2MField instead并避免了手动创建列表等的需要（并且获得了更好的性能，也使得ORM可以优化查询）。

Answer 2

我认为您需要将循环内的all_images列表清空为：

def getalbum(self,request):
   albums=Album.objects.filter(user=request.user)
   album={}
   image_list={}
   all_results=[]
   for a in albums:
        album_images=AlbumImage.objects.filter(album=a)
        all_images = []
        for i in album_images:
            image_object=Upload.objects.get(id=str(i.image))
            image_list=str(image_object.image)
            all_images.append(image_list)
        album[a.name]=all_images
    all_results.append(album)
    return Response(all_results)

Answer 3

因为'all_images'是一个列表，而list在Python中是可变的。在内部循环中，当您添加“ all_images”列表时，无论引用到何处，它也会更新。同样，这也不是获取所需信息的正确方法。了解Django中的序列化器，并在这种情况下使用它们。 https://www.django-rest-framework.org/api-guide/serializers/

追加两个for循环Django

3 个答案: