Django提供了翻页器。用Django的Paginator类实现
一、views模块导入Paginator类实现数据分页
ApiTest/apiviews.py
每行都加了注释，希望有助于理解。
from django.shortcuts import render
from ApiTest.models import ApiTest
from django.contrib.auth.decorators import login_required
from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger, InvalidPage
@login_required
def api_test_manage(request):
username = request.session.get(\'user\', \'\')
# 获取所有接口测试数据
apitest_list = ApiTest.objects.all().order_by(\'id\')
# 生成Paginator对象对数据分页，每页显示10条数据
paginator = Paginator(apitest_list,10)
# 使用request.GET.get()函数获取url中的page参数的数值。默认第1页
page = request.GET.get(\'page\', 1)
# 把获取的当前页码数转换成整数类型
current_page = int(page)
try:
# 获取查询页数的接口数据列表，page()函数会判断page实参是否是有效数字。page()函数源码附在文章的最后
apitest_list = paginator.page(page)
except PageNotAnInteger:
apitest_list = paginator.page(1)
except (EmptyPage, InvalidPage):
# paginator.num_pages
apitest_list = paginator.page(paginator.num_pages)
return render(request, \"apitest_manage.html\", {\'user\': username, \'apitests\': apitest_list})
二、将views的数据渲染到前端模板上
在对应的html文件中加入此段代码即可。
<div class=\"container\">
<ul class=\"pagination\" id=\"pager\">
{# 上一页链接 #}
{% if apitests.has_previous %}
<li class=\"previous\"><a href=\"/apitest_manage/?page={{ apitests.previous_page_number }}\" rel=\"external nofollow\" >上一页</a></li>
{% else %}
<li class=\"previous disabled\"><a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" >上一页</a></li>
{% endif %}
{# 中间数字显示 #}
{% for num in apitests.paginator.page_range %}
{% if num == currentPage %}
<li class=\"item active\"><a href=\"/apitest_manage/?page={{ num }}\" rel=\"external nofollow\" rel=\"external nofollow\" >{{ num }}</a></li>
{% else %}
<li class=\"item\"><a href=\"/apitest_manage/?page={{ num }}\" rel=\"external nofollow\" rel=\"external nofollow\" >{{ num }}</a></li>
{% endif %}
{% endfor %}
{# 下一页链接 #}
{% if apitests.has_next %} {# 如果有下一页，则正常显示下一页链接 #}
<li class=\"next\"><a href=\"/apitest_manage/?page={{ apitests.next_page_number }}\" rel=\"external nofollow\" >下一页</a></li>
{% else %}
<li class=\"next disabled\"><a href=\"#\" rel=\"external nofollow\" rel=\"external nofollow\" >下一页</a></li>
{% endif %}
</ul>
</div>
三、效果展示
四、Paginator类源码
此类主要用在views文件
class Paginator:
def __init__(self, object_list, per_page, orphans=0,
allow_empty_first_page=True):
self.object_list = object_list
self._check_object_list_is_ordered()
self.per_page = int(per_page)
self.orphans = int(orphans)
self.allow_empty_first_page = allow_empty_first_page
def validate_number(self, number):
\"\"\"Validate the given 1-based page number.\"\"\"
try:
if isinstance(number, float) and not number.is_integer():
raise ValueError
number = int(number)
except (TypeError, ValueError):
raise PageNotAnInteger(_(\'That page number is not an integer\'))
if number < 1:
raise EmptyPage(_(\'That page number is less than 1\'))
if number > self.num_pages:
if number == 1 and self.allow_empty_first_page:
pass
else:
raise EmptyPage(_(\'That page contains no results\'))
return number
def get_page(self, number):
\"\"\"
Return a valid page, even if the page argument isn\'t a number or isn\'t
in range.
\"\"\"
try:
number = self.validate_number(number)
except PageNotAnInteger:
number = 1
except EmptyPage:
number = self.num_pages
return self.page(number)
def page(self, number):
\"\"\"Return a Page object for the given 1-based page number.\"\"\"
number = self.validate_number(number)
bottom = (number - 1) * self.per_page
top = bottom + self.per_page
if top + self.orphans >= self.count:
top = self.count
return self._get_page(self.object_list[bottom:top], number, self)
def _get_page(self, *args, **kwargs):
\"\"\"
Return an instance of a single page.
This hook can be used by subclasses to use an alternative to the
standard :cls:`Page` object.
\"\"\"
return Page(*args, **kwargs)
@cached_property
def count(self):
\"\"\"Return the total number of objects, across all pages.\"\"\"
c = getattr(self.object_list, \'count\', None)
if callable(c) and not inspect.isbuiltin(c) and method_has_no_args(c):
return c()
return len(self.object_list)
@cached_property
def num_pages(self):
\"\"\"Return the total number of pages.\"\"\"
if self.count == 0 and not self.allow_empty_first_page:
return 0
hits = max(1, self.count - self.orphans)
return ceil(hits / self.per_page)
@property
def page_range(self):
\"\"\"
Return a 1-based range of pages for iterating through within
a template for loop.
\"\"\"
return range(1, self.num_pages + 1)
def _check_object_list_is_ordered(self):
\"\"\"
Warn if self.object_list is unordered (typically a QuerySet).
\"\"\"
ordered = getattr(self.object_list, \'ordered\', None)
if ordered is not None and not ordered:
obj_list_repr = (
\'{} {}\'.format(self.object_list.model, self.object_list.__class__.__name__)
if hasattr(self.object_list, \'model\')
else \'{!r}\'.format(self.object_list)
)
warnings.warn(
\'Pagination may yield inconsistent results with an unordered \'
\'object_list: {}.\'.format(obj_list_repr),
UnorderedObjectListWarning,
stacklevel=3
)
五、Page类源码
此类主要用在html文件
class Page(collections.abc.Sequence):
def __init__(self, object_list, number, paginator):
self.object_list = object_list
self.number = number
self.paginator = paginator
def __repr__(self):
return \'<Page %s of %s>\' % (self.number, self.paginator.num_pages)
def __len__(self):
return len(self.object_list)
def __getitem__(self, index):
if not isinstance(index, (int, slice)):
raise TypeError(
\'Page indices must be integers or slices, not %s.\'
% type(index).__name__
)
# The object_list is converted to a list so that if it was a QuerySet
# it won\'t be a database hit per __getitem__.
if not isinstance(self.object_list, list):
self.object_list = list(self.object_list)
return self.object_list[index]
def has_next(self):
return self.number < self.paginator.num_pages
def has_previous(self):
return self.number > 1
def has_other_pages(self):
return self.has_previous() or self.has_next()
def next_page_number(self):
return self.paginator.validate_number(self.number + 1)
def previous_page_number(self):
return self.paginator.validate_number(self.number - 1)
def start_index(self):
\"\"\"
Return the 1-based index of the first object on this page,
relative to total objects in the paginator.
\"\"\"
# Special case, return zero if no items.
if self.paginator.count == 0:
return 0
return (self.paginator.per_page * (self.number - 1)) + 1
def end_index(self):
\"\"\"
Return the 1-based index of the last object on this page,
relative to total objects found (hits).
\"\"\"
# Special case for the last page because there can be orphans.
if self.number == self.paginator.num_pages:
return self.paginator.count
return self.number * self.paginator.per_page
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