无限分类

#1.方式1
data=[
    {"cat_id":1,"name":"北京","parent_id":0},
    {"cat_id":2,"name":"上海","parent_id":0},
    {"cat_id":3,"name":"沙河","parent_id":1},
    {"cat_id":4,"name":"sb镇","parent_id":3},
    {"cat_id":5,"name":"昌平","parent_id":1},
    {"cat_id":6,"name":"青浦","parent_id":2},
]
def get_level(data):
    data_list=[]
    for item in data:
        if item[‘parent_id‘]==0:
            item[‘level‘]=0
        else:
            item[‘level‘]=1
        data_list.append(item)
    return data_list
# print(1,get_level(data))
‘‘‘
问题：
因为前端，需要通过循环多少成来，展示多个等级
for item in data:
    print(item.name)
    for item1 in item.children 
        item1.name
        
归档：我要把我的子集，都放在我的children列表里面          
‘‘‘

#方式2
data=[
    {"cat_id":1,"name":"北京","parent_id":0},
    {"cat_id":2,"name":"上海","parent_id":0},
    {"cat_id":3,"name":"沙河","parent_id":1},
    {"cat_id":4,"name":"sb镇","parent_id":3},
    {"cat_id":5,"name":"昌平","parent_id":1},
    {"cat_id":6,"name":"青浦","parent_id":2},
]
def get_tree(data):
    lists=[]
    tree={}
    for i in data:
        tree[i[‘cat_id‘]]=i
    # print(tree)
    for item in data:
        if not item[‘parent_id‘]:
            lists.append(tree[item[‘cat_id‘]])
        else:
            if "children" not in tree[item[‘parent_id‘]]:
                tree[item[‘parent_id‘]][‘children‘]=[]
            tree[item[‘parent_id‘]][‘children‘].append(tree[item[‘cat_id‘]])
    return lists

print(2,get_tree(data))
[
    {‘cat_id‘: 1, ‘name‘: ‘北京‘, ‘parent_id‘: 0,
     ‘children‘: [{‘cat_id‘: 3, ‘name‘: ‘沙河‘, ‘parent_id‘: 1,
                    ‘children‘: [{‘cat_id‘: 4, ‘name‘: ‘sb镇‘, ‘parent_id‘: 3}]
    },
         {‘cat_id‘: 5, ‘name‘: ‘昌平‘, ‘parent_id‘: 1}]},
         {‘cat_id‘: 2, ‘name‘: ‘上海‘, ‘parent_id‘: 0, ‘children‘: [{‘cat_id‘: 6, ‘name‘: ‘青浦‘, ‘parent_id‘: 2}]}
]


#方式3
#需求
‘‘‘
问题：
我们数据不是有序的，但是我们要排序，并归类，把父集放在子集的前面，辈分等级通过level标明

‘‘‘



res=[]
def get_son(data,level=0,parent_id=0,is_clear=True):
    if is_clear:
        res.clear()
    for item in data:
        if item[‘parent_id‘]==parent_id:
            item[‘level‘]=level
            res.append(item)
            get_son(data,level=level+1,parent_id=item[‘cat_id‘],is_clear=False)
    return res

# son=get_son(data)
# for i in son:
#     print("-"*i[‘level‘]+i[‘name‘])
# 1北京 0
#     2-海淀1
#         4--sb镇2
#     -昌平
# 3 上海 0
#     -青浦
#     --徐泾镇
#     -闵行
res_id=[]
def get_son_id(data,parent_id=0,is_clear=True):
    if is_clear:
        res_id.clear()
        if parent_id :
            res_id.append(parent_id)

    for item in data:
        if item[‘parent_id‘]==parent_id:
            res_id.append(item[‘cat_id‘])
            get_son_id(data,parent_id=item[‘cat_id‘],is_clear=False)
    return res_id
# print(get_son_id(data,1))

# import time ,random
# def get_order_id():
#     st="012345679qwertyui"
#     order_id=str(time.strftime("%Y%m%d%h%M%S"))+"".join(random.sample(st,5))
#     return order_id
# from datetime import datetime
#
# from pro_celery.celery import del_order
# def add_task(order_id,seconds=5):
#     ctime = datetime.now()
#     utc_ctime = datetime.utcfromtimestamp(ctime.timestamp())
#     from datetime import timedelta
#     time_delay = timedelta(seconds=seconds)
#     task_time = utc_ctime + time_delay
#     result = del_order.apply_async(args=[order_id, ], eta=task_time)