问题

我想在输出中获得我的类别列表的扁平列表，但这段代码没有做到。它仍然显示嵌套列表中的类别。有人可以帮助我吗？

这是代码：

@api_view(['GET'])
def AllCategoriesList(request):
    categories = Categories.objects.filter(parent=None).prefetch_related(
        Prefetch('children', queryset=Categories.objects.all(), to_attr='subcategories')
    )
    
    def flatten_list(lst):
        flat_lst = []
        for item in lst:
            if isinstance(item, list):
                flat_lst.extend(flatten_list(item))
            else:
                flat_lst.append(item)
		
        return flat_lst
    
    category_list = []
    for category in categories:
        category_list.append(category)
        category_list.extend(category.children.all())

    flattened_list = flatten_list(category_list)

    serializer = CategorieSerializer(flattened_list, many=True)
    return Response(serializer.data)

我尝试修改我的代码来使用flatten_list函数，但它不起作用。

这是输出：

 { "id": 1,
    "image_couverture": null,
    "children": [{ "id": 2,
        "image_couverture": null,
        "children": [],
        "nom_categorie": "nouveau categorie",
        "descriptions": "categorie fille",
        "slug": "nouveau-categorie",
        "created_at": "2023-03-04T08:08:35.667959Z",
        "updated_at": null,
        "parent": 1
      }
    ],
    "nom_categorie": "Test categorie",
    "descriptions": "test categorie",
    "slug": "test-categorie",
    "created_at": "2023-03-04T06:43:42.628255Z",
    "updated_at": null,
    "parent": null
  },
  {
    "id": 2,
    "image_couverture": null,
    "children": [],
    "nom_categorie": "nouveau categorie",
    "descriptions": "categorie fille",
    "slug": "nouveau-categorie",
    "created_at": "2023-03-04T08:08:35.667959Z",
    "updated_at": null,
    "parent": 1
  },
  {
    "id": 3,
    "image_couverture": null,
    "children": [
      {
        "id": 4,
        "image_couverture": null,
        "children": [],
        "nom_categorie": "Boissons",
        "descriptions": "Test description",
        "slug": "boissons",
        "created_at": "2023-03-06T10:13:39.229660Z",
        "updated_at": null,
        "parent": 3
      }
    ],
    "nom_categorie": "Alimentation & vins",
    "descriptions": "Test Description",
    "slug": "alimentation-vins",
    "created_at": "2023-03-06T10:06:24.492310Z",
    "updated_at": null,
    "parent": null
  },
  {
    "id": 4,
    "image_couverture": null,
    "children": [],
    "nom_categorie": "Boissons",
    "descriptions": "Test description",
    "slug": "boissons",
    "created_at": "2023-03-06T10:13:39.229660Z",
    "updated_at": null,
    "parent": 3
  },
  {
    "id": 5,
    "image_couverture": null,
    "children": [
      {
        "id": 13,
        "image_couverture": null,
        "children": [],
        "nom_categorie": "spa",
        "descriptions": "hotel bla",
        "slug": "spa",
        "created_at": "2023-03-07T16:54:15.145494Z",
        "updated_at": null,
        "parent": 5
      }
    ],
    "nom_categorie": "VOYAGES et LOCATIONS",
    "descriptions": "Test",
    "slug": "voyages-et-locations",
    "created_at": "2023-03-06T10:58:44.996614Z",
    "updated_at": null,
    "parent": null
  },
  {
    "id": 13,
    "image_couverture": null,
    "children": [],
    "nom_categorie": "spa",
    "descriptions": "hotel bla",
    "slug": "spa",
    "created_at": "2023-03-07T16:54:15.145494Z",
    "updated_at": null,
    "parent": 5
  },
  {
    "id": 6,
    "image_couverture": null,
    "children": [
      {
        "id": 12,
        "image_couverture": null,
        "children": [],
        "nom_categorie": "Ballon",
        "descriptions": "gfjfm jtukj gfdf",
        "slug": "ballon",
        "created_at": "2023-03-06T18:28:25.832572Z",
        "updated_at": null,
        "parent": 6
      }
    ],
    "nom_categorie": "SPORTS et FITNESS",
    "descriptions": "Test",
    "slug": "sports-et-fitness",
    "created_at": "2023-03-06T10:59:26.929241Z",
    "updated_at": null,
    "parent": null
  },
  {
    "id": 12,
    "image_couverture": null,
    "children": [],
    "nom_categorie": "Ballon",
    "descriptions": "gfjfm jtukj gfdf",
    "slug": "ballon",
    "created_at": "2023-03-06T18:28:25.832572Z",
    "updated_at": null,
    "parent": 6
  },
  {
    "id": 7,
    "image_couverture": null,
    "children": [
      {
        "id": 8,
        "image_couverture": null,
        "children": [],
        "nom_categorie": "Chaussures femme",
        "descriptions": "Test",
        "slug": "chaussures-femme",
        "created_at": "2023-03-06T11:15:08.421713Z",
        "updated_at": null,
        "parent": 7
      }
    ],
    "nom_categorie": "MODE FEMME",
    "descriptions": "Test",
    "slug": "mode-femme",
    "created_at": "2023-03-06T11:13:09.847437Z",
    "updated_at": null,
    "parent": null
  },
  {
    "id": 8,
    "image_couverture": null,


<details>
<summary>英文:</summary>

I want a flat list for my categories list in output, but this code doesn&#39;t do that. It still shows the categories in imbricated list. Can someone help me?

This is the code: 
```python
@api_view([&#39;GET&#39;])
def AllCategoriesList(request):
    categories = Categories.objects.filter(parent=None).prefetch_related(
        Prefetch(&#39;children&#39;, queryset=Categories.objects.all(), to_attr=&#39;subcategories&#39;)
    )
    
    def flatten_list(lst):
        flat_lst = []
        for item in lst:
            if isinstance(item, list):
                flat_lst.extend(flatten_list(item))
            else:
                flat_lst.append(item)
		
        return flat_lst
    
    category_list = []
    for category in categories:
        category_list.append(category)
        category_list.extend(category.children.all())

    flattened_list = flatten_list(category_list)

    serializer = CategorieSerializer(flattened_list, many=True)
    return Response(serializer.data)

I tried to change my code to use the flatten_list function, but it doesn't work.

This is the output:

 { "id": 1,
"image_couverture": null,
"children": [{ "id": 2,
"image_couverture": null,
"children": [],
"nom_categorie": "nouveau categorie",
"descriptions": "categorie fille",
"slug": "nouveau-categorie",
"created_at": "2023-03-04T08:08:35.667959Z",
"updated_at": null,
"parent": 1
}
],
"nom_categorie": "Test categorie",
"descriptions": "test categorie",
"slug": "test-categorie",
"created_at": "2023-03-04T06:43:42.628255Z",
"updated_at": null,
"parent": null
},
{
"id": 2,
"image_couverture": null,
"children": [],
"nom_categorie": "nouveau categorie",
"descriptions": "categorie fille",
"slug": "nouveau-categorie",
"created_at": "2023-03-04T08:08:35.667959Z",
"updated_at": null,
"parent": 1
},
{
"id": 3,
"image_couverture": null,
"children": [
{
"id": 4,
"image_couverture": null,
"children": [],
"nom_categorie": "Boissons",
"descriptions": "Test description",
"slug": "boissons",
"created_at": "2023-03-06T10:13:39.229660Z",
"updated_at": null,
"parent": 3
}
],
"nom_categorie": "Alimentation & vins",
"descriptions": "Test Description",
"slug": "alimentation-vins",
"created_at": "2023-03-06T10:06:24.492310Z",
"updated_at": null,
"parent": null
},
{
"id": 4,
"image_couverture": null,
"children": [],
"nom_categorie": "Boissons",
"descriptions": "Test description",
"slug": "boissons",
"created_at": "2023-03-06T10:13:39.229660Z",
"updated_at": null,
"parent": 3
},
{
"id": 5,
"image_couverture": null,
"children": [
{
"id": 13,
"image_couverture": null,
"children": [],
"nom_categorie": "spa",
"descriptions": "hotel bla",
"slug": "spa",
"created_at": "2023-03-07T16:54:15.145494Z",
"updated_at": null,
"parent": 5
}
],
"nom_categorie": "VOYAGES et LOCATIONS",
"descriptions": "Test",
"slug": "voyages-et-locations",
"created_at": "2023-03-06T10:58:44.996614Z",
"updated_at": null,
"parent": null
},
{
"id": 13,
"image_couverture": null,
"children": [],
"nom_categorie": "spa",
"descriptions": "hotel bla",
"slug": "spa",
"created_at": "2023-03-07T16:54:15.145494Z",
"updated_at": null,
"parent": 5
},
{
"id": 6,
"image_couverture": null,
"children": [
{
"id": 12,
"image_couverture": null,
"children": [],
"nom_categorie": "Ballon",
"descriptions": "gfjfm jtukj gfdf",
"slug": "ballon",
"created_at": "2023-03-06T18:28:25.832572Z",
"updated_at": null,
"parent": 6
}
],
"nom_categorie": "SPORTS et FITNESS",
"descriptions": "Test",
"slug": "sports-et-fitness",
"created_at": "2023-03-06T10:59:26.929241Z",
"updated_at": null,
"parent": null
},
{
"id": 12,
"image_couverture": null,
"children": [],
"nom_categorie": "Ballon",
"descriptions": "gfjfm jtukj gfdf",
"slug": "ballon",
"created_at": "2023-03-06T18:28:25.832572Z",
"updated_at": null,
"parent": 6
},
{
"id": 7,
"image_couverture": null,
"children": [
{
"id": 8,
"image_couverture": null,
"children": [],
"nom_categorie": "Chaussures femme",
"descriptions": "Test",
"slug": "chaussures-femme",
"created_at": "2023-03-06T11:15:08.421713Z",
"updated_at": null,
"parent": 7
}
],
"nom_categorie": "MODE FEMME",
"descriptions": "Test",
"slug": "mode-femme",
"created_at": "2023-03-06T11:13:09.847437Z",
"updated_at": null,
"parent": null
},
{
"id": 8,
"image_couverture": null,
"children": [],
"nom_categorie": "Chaussures femme",
"descriptions": "Test",
"slug": "chaussures-femme",
"created_at": "2023-03-06T11:15:08.421713Z",
"updated_at": null,
"parent": 7
},
{
"id": 9,
"image_couverture": null,
"children": [
{
"id": 10,
"image_couverture": null,
"children": [],
"nom_categorie": "tafita-1",
"descriptions": "hgjjgj",
"slug": "tafita1",
"created_at": "2023-03-06T18:15:23.355740Z",
"updated_at": null,
"parent": 9
}
],
"nom_categorie": "tafita",
"descriptions": "nljbk",
"slug": "tafita",
"created_at": "2023-03-06T18:14:58.259709Z",
"updated_at": null,
"parent": null
},
{
"id": 10,
"image_couverture": null,
"children": [],
"nom_categorie": "tafita-1",
"descriptions": "hgjjgj",
"slug": "tafita1",
"created_at": "2023-03-06T18:15:23.355740Z",
"updated_at": null,
"parent": 9
},
{
"id": 11,
"image_couverture": null,
"children": [],
"nom_categorie": "Tech",
"descriptions": "gd hgjkjg th",
"slug": "tech",
"created_at": "2023-03-06T18:25:00.949297Z",
"updated_at": null,
"parent": null
},
{
"id": 14,
"image_couverture": null,
"children": [],
"nom_categorie": "Hotel34",
"descriptions": "DJGJ JGKJ",
"slug": "hotel34",
"created_at": "2023-03-07T16:57:03.666177Z",
"updated_at": null,
"parent": null
}
]

答案1

得分: 0

以下是翻译的代码部分：

def flatten_list(data):
    flat_lst = []

    if isinstance(data, list):
        for item in data:
            flat_lst.append(item)
            flat_lst.extend(flatten_list(item))
        return flat_lst

    if isinstance(data, dict):
        ## ----------------------
        ## 使用项目的副本，以便我们不直接
        ## 迭代字典
        ## ----------------------
        for key, value in list(data.items()):
            flat_lst.extend(flatten_list(value))

            ### ----------------------
            ### 你不想要 "children": []
            ### ----------------------
            if isinstance(value, list):
                del data[key]
            ### ----------------------
        ## ----------------------

    return flat_lst

data = json.loads(data_raw)
data = flatten_list(data)

## ---------------
## 仅唯一的项目（按id）
## ---------------
data = list({item["id"]: item for item in data}.values())
## ---------------

print(json.dumps(data, indent=4))

希望这对您有所帮助。

data_raw = """
[
{
"id": 1,
"image_couverture": null,
"children": [
{
"id": 2,
"image_couverture": null,
"children": [],
"nom_categorie": "nouveau categorie",
"descriptions": "categorie fille",
"slug": "nouveau-categorie",
"created_at": "2023-03-04T08:08:35.667959Z",
"updated_at": null,
"parent": 1
}
],
"nom_categorie": "Test categorie",
"descriptions": "test categorie",
"slug": "test-categorie",
"created_at": "2023-03-04T06:43:42.628255Z",
"updated_at": null,
"parent": null
},
{
"id": 2,
"image_couverture": null,
"children": [],
"nom_categorie": "nouveau categorie",
"descriptions": "categorie fille",
"slug": "nouveau-categorie",
"created_at": "2023-03-04T08:08:35.667959Z",
"updated_at": null,
"parent": 1
},
{
"id": 3,
"image_couverture": null,
"children": [
{
"id": 4,
"image_couverture": null,
"children": [],
"nom_categorie": "Boissons",
"descriptions": "Test description",
"slug": "boissons",
"created_at": "2023-03-06T10:13:39.229660Z",
"updated_at": null,
"parent": 3
}
],
"nom_categorie": "Alimentation & vins",
"descriptions": "Test Description",
"slug": "alimentation-vins",
"created_at": "2023-03-06T10:06:24.492310Z",
"updated_at": null,
"parent": null
},
{
"id": 4,
"image_couverture": null,
"children": [],
"nom_categorie": "Boissons",
"descriptions": "Test description",
"slug": "boissons",
"created_at": "2023-03-06T10:13:39.229660Z",
"updated_at": null,
"parent": 3
},
{
"id": 5,
"image_couverture": null,
"children": [
{
"id": 13,
"image_couverture": null,
"children": [],
"nom_categorie": "spa",
"descriptions": "hotel bla",
"slug": "spa",
"created_at": "2023-03-07T16:54:15.145494Z",
"updated_at": null,
"parent": 5
}
],
"nom_categorie": "VOYAGES et LOCATIONS",
"descriptions": "Test",
"slug": "voyages-et-locations",
"created_at": "2023-03-06T10:58:44.996614Z",
"updated_at": null,
"parent": null
},
{
"id": 13,
"image_couverture": null,
"children": [],
"nom_categorie": "spa",
"descriptions": "hotel bla",
"slug": "spa",
"created_at": "2023-03-07T16:54:15.145494Z",
"updated_at": null,
"parent": 5
},
{
"id": 6,
"image_couverture": null,
"children": [
{
"id": 12,
"image_couverture": null,
"children": [],
"nom_categorie": "Ballon",
"descriptions": "gfjfm jtukj gfdf",
"slug": "ballon",
"created_at": "2023-03-06T18:28:25.832572Z",
"updated_at": null,
"parent": 6
}
],
"nom_categorie": "SPORTS et FITNESS",
"descriptions": "Test",
"slug": "sports-et-fitness",
"created_at": "2023-03-06T10:59:26.929241Z",
"updated_at": null,
"parent": null
},
{
"id": 12,
"image_couverture": null,
"children": [],
"nom_categorie": "Ballon",
"descriptions": "gfjfm jtukj gfdf",
"slug": "ballon",
"created_at": "2023-03-06T18:28:25.832572Z",
"updated_at": null,
"parent": 6
},
{
"id": 7,
"image_couverture": null,
"children": [
{
"id": 8,
"image_couverture": null,
"children": [],
"nom_categorie": "Chaussures femme",
"descriptions": "Test",
"slug": "chaussures-femme",
"created_at": "2023-03-06T11:15:08.421713Z",
"updated_at": null,
"parent": 7
}
],
"nom_categorie": "MODE FEMME",
"descriptions": "Test",
"slug": "mode-femme",
"created_at": "2023-03-06T11:13:09.847437Z",
"updated_at": null,
"parent": null
},
{
"id": 8,
"image_couverture": null,
"children": [],
"nom_categorie": "Chaussures femme",
"descriptions": "Test",
"slug": "chaussures-femme",
"created_at": "2023-03-06T11:15:08.421713Z",
"updated_at": null,
"parent": 7
},
{
"id": 9,
"image_couverture": null,
"children": [
{
"id": 10,
"image_couverture": null,
"children": [],
"nom_categorie": "tafita-1",
"descriptions": "hgjjgj",
"slug": "tafita1",
"created_at": "2023-03-06T18:15:23.355740Z",
"updated_at": null,
"parent": 9
}
],
"nom_categorie": "tafita",
"descriptions": "nljbk",
"slug": "tafita",
"created_at": "2023-03-06T18:14:58.259709Z",
"updated_at": null,
"parent": null
},
{
"id": 10,
"image_couverture": null,
"children": [],
"nom_categorie": "tafita-1",
"descriptions": "hgjjgj",
"slug": "tafita1",
"created_at": "2023-03-06T18:15:23.355740Z",
"updated_at": null,
"parent": 9
},
{
"id": 11,
"image_couverture": null,
"children": [],
"nom_categorie": "Tech",
"descriptions": "gd hgjkjg th",
"slug": "tech",
"created_at": "2023-03-06T18:25:00.949297Z",
"updated_at": null,
"parent": null
},
{
"id": 14,
"image_couverture": null,
"children": [],
"nom_categorie": "Hotel34",
"descriptions": "DJGJ JGKJ",
"slug": "hotel34",
"created_at": "2023-03-07T16:57:03.666177Z",
"updated_at": null,
"parent": null
}
]
"""

def flatten_list(data):
    flat_lst = []

    if isinstance(data, list):
        for item in data:
            flat_lst.append(item)
            flat_lst.extend(flatten_list(item))
        return flat_lst

    if isinstance(data, dict):
        ## ----------------------
        ## Use a copy of the items so we are not directly
        ## iterating over the dictionary
        ## ----------------------
        for key, value in list(data.items()):
            flat_lst.extend(flatten_list(value))

            ### ----------------------
            ### you don't want children": []
            ### ----------------------
            if isinstance(value, list):
                del data[key]
            ### ----------------------
        ## ----------------------
    
    return flat_lst

data = json.loads(data_raw)
data = flatten_list(data)

## ---------------
## just the unique items (by id)
## ---------------
data = list({item["id"]: item for item in data}.values())
## ---------------

print(json.dumps(data, indent=4))

[
{
"id": 1,
"image_couverture": null,
"nom_categorie": "Test categorie",
"descriptions": "test categorie",
"slug": "test-categorie",
"created_at": "2023-03-04T06:43:42.628255Z",
"updated_at": null,
"parent": null
},
{
"id": 2,
"image_couverture": null,
"nom_categorie": "nouveau categorie",
"descriptions": "categorie fille",
"slug": "nouveau-categorie",
"created_at": "2023-03-04T08:08:35.667959Z",
"updated_at": null,
"parent": 1
},
{
"id": 3,
"image_couverture": null,
"nom_categorie": "Alimentation & vins",
"descriptions": "Test Description",
"slug": "alimentation-vins",
"created_at": "2023-03-06T10:06:24.492310Z",
"updated_at": null,
"parent": null
},
{
"id": 4,
"image_couverture": null,
"nom_categorie": "Boissons",
"descriptions": "Test description",
"slug": "boissons",
"created_at": "2023-03-06T10:13:39.229660Z",
"updated_at": null,
"parent": 3
},
{
"id": 5,
"image_couverture": null,
"nom_categorie": "VOYAGES et LOCATIONS",
"descriptions": "Test",
"slug": "voyages-et-locations",
"created_at": "2023-03-06T10:58:44.996614Z",
"updated_at": null,
"parent": null
},
{
"id": 13,
"image_couverture": null,
"nom_categorie": "spa",
"descriptions": "hotel bla",
"slug": "spa",
"created_at": "2023-03-07T16:54:15.145494Z",
"updated_at": null,
"parent": 5
},
{
"id": 6,
"image_couverture": null,
"nom_categorie": "SPORTS et FITNESS",
"descriptions": "Test",
"slug": "sports-et-fitness",
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