Django之分页器组件
class Pagination(object):
def __init__(self,current_page,all_count,per_page_num=2,pager_count=11):
"""
封装分页相关数据
:param current_page: 当前页
:param all_count: 数据库中的数据总条数
:param per_page_num: 每页显示的数据条数
:param pager_count: 最多显示的页码个数
用法:
queryset = model.objects.all()
page_obj = Pagination(current_page,all_count)
page_data = queryset[page_obj.start:page_obj.end]
获取数据用page_data而不再使用原始的queryset
获取前端分页样式用page_obj.page_html
"""
try:
current_page = int(current_page)
except Exception as e:
current_page = 1
if current_page <1:
current_page = 1
self.current_page = current_page
self.all_count = all_count
self.per_page_num = per_page_num
# 总页码
all_pager, tmp = divmod(all_count, per_page_num)
if tmp:
all_pager += 1
self.all_pager = all_pager
self.pager_count = pager_count
self.pager_count_half = int((pager_count - 1) / 2)
@property
def start(self):
return (self.current_page - 1) * self.per_page_num
@property
def end(self):
return self.current_page * self.per_page_num
def page_html(self):
# 如果总页码 < 11个：
if self.all_pager <= self.pager_count:
pager_start = 1
pager_end = self.all_pager + 1
# 总页码 > 11
else:
# 当前页如果<=页面上最多显示11/2个页码
if self.current_page <= self.pager_count_half:
pager_start = 1
pager_end = self.pager_count + 1
# 当前页大于5
else:
# 页码翻到最后
if (self.current_page + self.pager_count_half) > self.all_pager:
pager_end = self.all_pager + 1
pager_start = self.all_pager - self.pager_count + 1
else:
pager_start = self.current_page - self.pager_count_half
pager_end = self.current_page + self.pager_count_half + 1
page_html_list = []
# 添加前面的nav和ul标签
page_html_list.append('''
<nav aria-label='Page navigation>'
<ul class='pagination'>
''')
first_page = '<li><a href="?page=%s">首页</a></li>' % (1)
page_html_list.append(first_page)
if self.current_page <= 1:
prev_page = '<li class="disabled"><a href="#">上一页</a></li>'
else:
prev_page = '<li><a href="?page=%s">上一页</a></li>' % (self.current_page - 1,)
page_html_list.append(prev_page)
for i in range(pager_start, pager_end):
if i == self.current_page:
temp = '<li class="active"><a href="?page=%s">%s</a></li>' % (i, i,)
else:
temp = '<li><a href="?page=%s">%s</a></li>' % (i, i,)
page_html_list.append(temp)
if self.current_page >= self.all_pager:
next_page = '<li class="disabled"><a href="#">下一页</a></li>'
else:
next_page = '<li><a href="?page=%s">下一页</a></li>' % (self.current_page + 1,)
page_html_list.append(next_page)
last_page = '<li><a href="?page=%s">尾页</a></li>' % (self.all_pager,)
page_html_list.append(last_page)
# 尾部添加标签
page_html_list.append('''
</nav>
</ul>
''')
return ''.join(page_html_list)
自定义分页器组件
paging.py
from django.utils.safestring import mark_safe
class Paging:
def __init__(self, total_count, per_page_count, per_page_page, current_page, data=None):
"""
:param current_page: 当前页码
:param total_count: 总数据量
:param per_page_count: 每页显示多少条
:param per_page_page: 总共显示多少个页码
data: 可编辑Queryset对象
start_page_number:起始页码
end_page_number:结束页码
"""
try:
current_page = int(current_page)
except Exception:
current_page = 1
half_number = per_page_page // 2
a, b = divmod(total_count, per_page_count)
# 如果余数不为0，页码总数为商+1
if b:
total_page_count = a + 1
else:
total_page_count = a
# total_page_count 最大页数
# 当当前页码小于等于0的时候，默认显示第一页
if current_page >= total_page_count:
current_page = total_page_count
if current_page <= 0:
current_page = 1
# current_page 2
# print(total_page_count) # 2
start_page_number = current_page - half_number #
end_page_number = current_page + half_number + 1 # 6
if start_page_number <= 0:
start_page_number = 1
end_page_number = per_page_page + 1 # 7
if end_page_number >= total_page_count: # 6 > 2
start_page_number = total_page_count - per_page_page + 1 # -4
end_page_number = total_page_count + 1 # 3
if total_page_count < per_page_page:
start_page_number = 1
end_page_number = total_page_count + 1
self.current_page = current_page
self.per_page_count = per_page_count
self.total_page_count = total_page_count
self.start_page_number = start_page_number
self.end_page_number = end_page_number
self.data = data
@property
def start_data_number(self):
return (self.current_page - 1) * self.per_page_count
@property
def end_data_number(self):
return self.current_page * self.per_page_count
@property
def paging_html(self):
page_html = """
<nav aria-label="Page navigation">
<ul class="pagination">
"""
self.data["page"] = 1
first_page = f"""
<li>
<a href="?{self.data.urlencode()}" aria-label="Previous">
<span aria-hidden="true">首页</span>
</a>
</li>"""
page_html += first_page
self.data['page'] = self.current_page - 1
previous_page = f"""
<li>
<a href="?{self.data.urlencode()}" aria-label="Previous">
<span aria-hidden="true">«</span>
</a>
</li>"""
page_html += previous_page
for i in range(self.start_page_number, self.end_page_number):
self.data['page'] = i
if i == self.current_page:
page_html += f'<li class="active"><a href="?{self.data.urlencode()}">{i}</a></li>'
else:
page_html += f'<li><a href="?{self.data.urlencode()}">{i}</a></li>'
self.data['page'] = self.current_page + 1
next_page = f"""
<li>
<a href="?{self.data.urlencode()}" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li>
"""
page_html += next_page
self.data['page'] = self.total_page_count
last_page = f"""
<li>
<a href="?{self.data.urlencode()}" aria-label="Previous">
<span aria-hidden="true">尾页</span>
</a>
</li>"""
page_html += last_page
page_html += """
</ul>
</nav>
"""
return mark_safe(page_html)
views
entry_obj = models.Enrollment.objects.all()
page = request.GET.get("page") #当前页面
total_count = entry_obj.count() #总数据数
per_page_count = 10 #每页显示数据条数
per_page_page = 7 #每页页码显示
data = copy.copy(request.GET) #可编辑Queryset对象
page_obj = Paging(total_count, per_page_count, per_page_page, page, data) #实例化分页对象，参数是位置参数，一一对应
entry_obj=entry_obj[
page_obj.start_data_number:page_obj.end_data_number]
#。。。。
page_html = page_obj.paging_html #生成分页HTML标签