原文链接:https://blog.csdn.net/weixin_36380516/article/details/80295101
在web开发中,Flask web项目中实现分页,使用py编写。
首先,自定义一个分页工具类page_utils:
class Pagination(object):
def __init__(self, current_page, total_count, base_url, params, per_page_count=5, max_pager_count=11):
try:
current_page = int(current_page)
except Exception as e:
current_page = 1
if current_page <= 0:
current_page = 1
self.current_page = current_page
# 数据总条数
self.total_count = total_count
# 每页显示10条数据
self.per_page_count = per_page_count
# 页面上应该显示的最大页码
max_page_num, div = divmod(total_count, per_page_count)
if div:
max_page_num += 1
self.max_page_num = max_page_num
# 页面上默认显示11个页码(当前页在中间)
self.max_pager_count = max_pager_count
self.half_max_pager_count = int((max_pager_count - 1) / 2)
# URL前缀
self.base_url = base_url
# request.GET
import copy
params = copy.deepcopy(params)
get_dict = params.to_dict()
self.params = get_dict
@property
def start(self):
return (self.current_page - 1) * self.per_page_count
@property
def end(self):
return self.current_page * self.per_page_count
def page_html(self):
# 如果总页数 <= 11
if self.max_page_num <= self.max_pager_count:
pager_start = 1
pager_end = self.max_page_num
# 如果总页数 > 11
else:
# 如果当前页 <= 5
if self.current_page <= self.half_max_pager_count:
pager_start = 1
pager_end = self.max_pager_count
else:
# 当前页 + 5 > 总页码
if (self.current_page + self.half_max_pager_count) > self.max_page_num:
pager_end = self.max_page_num
pager_start = self.max_page_num - self.max_pager_count + 1 # 倒这数11个
else:
pager_start = self.current_page - self.half_max_pager_count
pager_end = self.current_page + self.half_max_pager_count
page_html_list = []
# {source:[2,], status:[2], gender:[2],consultant:[1],page:[1]}
# 首页
self.params['page'] = 1
first_page = '<li><a href="%s?%s">首页</a></li>' % (self.base_url, urlencode(self.params),)
page_html_list.append(first_page)
# 上一页
self.params["page"] = self.current_page - 1
if self.params["page"] < 1:
pervious_page = '<li class="disabled"><a href="%s?%s" aria-label="Previous">上一页</span></a></li>'%(self.base_url, urlencode(self.params))
else:
pervious_page = '<li><a href = "%s?%s" aria-label = "Previous" >上一页</span></a></li>' % (
self.base_url, urlencode(self.params))
page_html_list.append(pervious_page)
# 中间页码
for i in range(pager_start, pager_end + 1):
self.params['page'] = i
if i == self.current_page:
temp = '<li class="active"><a href="%s?%s">%s</a></li>' % (self.base_url, urlencode(self.params), i,)
else:
temp = '<li><a href="%s?%s">%s</a></li>' % (self.base_url, urlencode(self.params), i,)
page_html_list.append(temp)
# 下一页
self.params["page"] = self.current_page + 1
if self.params["page"] > self.max_page_num:
self.params["page"] = self.current_page
next_page = '<li class="disabled"><a href = "%s?%s" aria-label = "Next">下一页</span></a></li >' % (self.base_url, urlencode(self.params))
else:
next_page = '<li><a href = "%s?%s" aria-label = "Next">下一页</span></a></li>' % (
self.base_url, urlencode(self.params))
page_html_list.append(next_page)
# 尾页
self.params['page'] = self.max_page_num
last_page = '<li><a href="%s?%s">尾页</a></li>' % (self.base_url, urlencode(self.params),)
page_html_list.append(last_page)
return ''.join(page_html_list)
自定义方法中的参数:
current_page——表示当前页。
total_count——表示数据总条数。
base_url——表示分页URL前缀,请求的前缀获取可以通过Flask的request.path方法,无需自己指定。
例如:我们的路由方法为@app.route(’/test’),request.path方法即可获取/test。
params——表示请求传入的数据,params可以通过request.args动态获取。
例如:我们链接点击为:http://localhost:5000/test?page=10,此时request.args获取数据为ImmutableMultiDict([(‘page’, u’10’)])
per_page_count——指定每页显示数。
max_pager_count——指定页面最大显示页码
flask一个简单实战:
@application.route('/admin/blog-center/blogmanage')
@login_required
def blog_center_blogmanage():
#分页的对象
li = []
#从数据库中获得所有博文
blognums = Blog.query.count()
#以时间倒序的方式排列
blogs=Blog.query.order_by(Blog.create_time.desc())
#li列表内装的是每一条博文
for i in range(0, blognums):
li.append(blogs[i])
#per_page_count是每一页最多显示的条数
pager_obj = Pagination(request.args.get("page", 1), len(li), request.path, request.args, per_page_count=5)
index_list = li[pager_obj.start:pager_obj.end]
html = pager_obj.page_html()
return render_template('admin/blog-center-blogmanage.html',index_list=index_list, html=html)