Ajax运用与分页
django与ajax的分页处理
ajax + sweetAlert 实现再次确认:
下载插件 : https://github.com/lipis/bootstrap-sweetalert
二次确认的动态样式:
#样式: swal("删除成功!", "你可以准备跑路了!", "success");
#样式渲染 :基于bootstrap插件
缺陷: 创造者没有考虑中文,字体会被图标掩盖一部分,
解决 : 调节字体的边距!!
$("#b55").click(function () {
swal({
title: "你确定要删除吗?",
text: "删除可就找不回来了哦!",
type: "warning",
showCancelButton: true, // 是否显示取消按钮
confirmButtonClass: "btn-danger", // 确认按钮的样式类
confirmButtonText: "删除", // 确认按钮文本
cancelButtonText: "取消", // 取消按钮文本
closeOnConfirm: false, // 点击确认按钮不关闭弹框
showLoaderOnConfirm: true // 显示正在删除的动画效果
},
function () {
var deleteId = 2;
$.ajax({
url: "/delete_book/",
type: "post",
data: {"id": deleteId},
success: function (data) {
if (data.code === 0) {
swal("删除成功!", "你可以准备跑路了!", "success");
} else {
swal("删除失败", "你可以再尝试一下!", "error")
}
}
})
});
})
批量数据插入
bulk_create : 批量数据插入
数据插入 :
缺陷 : 手动写操作日志存库,每次都需要访问一次数据库,性能较差
改进 : 先存到缓存文件(对象),特定条件触发/定时写入数据库,
#样式 :
add_record_list=[]
f=utils.open_txt(cache_file_name)
for line in f.readlines():
record_line = json.loads(line)
#创建一个对象
obj =record(
user_name=record_line['user_name'],#操作人
operate_old_record=record_line['old_content'],#具体操作的内容(旧)
operate_now_record=record_line['new_content'],#具体操作的内容(新)
)
add_record_list.append(obj)
#批量写入数据
record.objects.bulk_create(add_record_list)
record 对象 / 文件
add_record_list : 数据(对象)
分页:
分页思路推导:
提高了用户体验,还是减轻数据库读取数据的压力
# 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)
# views 视图
from app01.utils.mypage import Pagination
def index(request):
book_queryset = models.Book.objects.all()
current_page = request.GET.get('page',1)
all_count = book_queryset.count()
page_obj = Pagination(current_page=current_page,all_count=all_count,per_page_num=10,pager_count=5)
page_queryset = book_queryset[page_obj.start:page_obj.end] # book_queryset = book_queryset[start_page:end_page]
return render(request,'index.html',locals())
#html 视图
#导入插件 :
<link rel="stylesheet" href="{% static 'bootstrap-3.3.7-dist/css/bootstrap.min.css' %}">
<link rel="stylesheet" href="{% static 'dist/sweetalert.css' %}">
<script src="{% static 'bootstrap-3.3.7-dist/js/bootstrap.min.js' %}"></script>
<script src="{% static 'dist/sweetalert.min.js' %}"></script>
div class="container-fluid">
<div class="row">
<div class="col-md-8 col-md-offset-2">
{% for book in page_queryset %} <!--将页面上原本的queryset数据全部换成切片之后的queryset即可-->
<p>{{ book }}</p>
{% endfor %}
{{ page_obj.page_html|safe }} <!---让前后端进行交互--->