一文教你使用Python实现本地分页

在项目开发的过程中，遇到分页的第一页就展示大量的数据，导致前端列表加载展示的速度慢，所以需要在本地加入分页处理，把所有数据先放到内存里，下面我用Python演示如何实现本地分页的算法（针对二级数据结构）

initialSize = 2 # 首屏展示条数eachSize = 5    # 剩余页展示条数local_pages = []  # 本地分页数据def makePage(d):    '''    制作分页数据    '''    local_pages.clear()    if calcSize(d) > initialSize: # 总条数大于首屏数，使用本地分页        sublist = []        for item in d:            for child in item["child"]:                sublist.append(child)                firstPageSize = min(len(sublist), initialSize) # 第一页的大小        local_pages.append(sublist[0:firstPageSize]) # 取第一页的集合        remain_size = len(sublist)-firstPageSize # 剩余条数        group_count = int(remain_size / eachSize) # 计算分页数        last_count = remain_size % eachSize # 取余，最后剩余多少条        idx = 0        for idx in range(group_count):            start = firstPageSize + idx * eachSize            end = start + eachSize            local_pages.append(sublist[start:end]) # 新增页集合        if last_count > 0:            local_pages.append(sublist[-last_count:]) # 余数不为0，将作为最后一页集合        pass                def calcSize(d)->int:    '''    计算总条数    '''    size = 0    for item in d:        size += len(item["child"]) + 1    return sizedef printPage():    '''    打印页面    '''    idx = 0    for p in local_pages:        idx += 1        print("page:{}".format(idx))        for item in p:            print(item)data = [{"id":"1",         "name":"parent_1",         "child":[             {"id":"1_1",              "name":"RS234326348264",              "parent_id":"1"              },             {"id":"1_2",              "name":"RS234326348264",              "parent_id":"1"              },             {"id":"1_3",              "name":"RS234326348264",              "parent_id":"1"              },             {"id":"1_4",              "name":"RS234326348264",              "parent_id":"1"              },              {"id":"1_5",              "name":"RS234326348264",              "parent_id":"1"              },              {"id":"1_6",              "name":"RS234326348264",              "parent_id":"1"              },              {"id":"1_7",              "name":"RS234326348264",              "parent_id":"1"              },              {"id":"1_8",              "name":"RS234326348264",              "parent_id":"1"              },              {"id":"1_9",              "name":"RS234326348264",              "parent_id":"1"              }]},        {"id":"2",         "name":"parent_2",         "child":[              {"id":"2_1",              "name":"RS234326348264",              "parent_id":"2"              }]}]print(f"首屏展示条数:{initialSize}")print(f"剩余页展示条数:{eachSize}")makePage(data)printPage()

打印结果

首屏展示条数:2
剩余页展示条数:5
page:1
{'id': '1_1', 'name': 'RS234326348264', 'parent_id': '1'}
{'id': '1_2', 'name': 'RS234326348264', 'parent_id': '1'}
page:2
{'id': '1_3', 'name': 'RS234326348264', 'parent_id': '1'}
{'id': '1_4', 'name': 'RS234326348264', 'parent_id': '1'}
{'id': '1_5', 'name': 'RS234326348264', 'parent_id': '1'}
{'id': '1_6', 'name': 'RS234326348264', 'parent_id': '1'}
{'id': '1_7', 'name': 'RS234326348264', 'parent_id': '1'}
page:3
{'id': '1_8', 'name': 'RS234326348264', 'parent_id': '1'}
{'id': '1_9', 'name': 'RS234326348264', 'parent_id': '1'}
{'id': '2_1', 'name': 'RS234326348264', 'parent_id': '2'}