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    Give Paginator a list of objects, plus the number of items you'd like tohave on each page, and it gives you methods for accessing the items for eachpage:

    注解

    Note that you can give Paginator a list/tuple, a Django QuerySet,or any other object with a count() or len() method. Whendetermining the number of objects contained in the passed object,Paginator will first try calling count(), then fallback to usinglen() if the passed object has no count() method. This allowsobjects such as Django's QuerySet to use a more efficient count()method when available.

    Here's a slightly more complex example using in a view topaginate a queryset. We give both the view and the accompanying template toshow how you can display the results. This example assumes you have aContacts model that has already been imported.

    The view function looks like this:

    In the template list.html, you'll want to include navigation betweenpages along with any interesting information from the objects themselves:

    Paginator 类的构造方法是:

    • class Paginator(object_list, per_page, orphans=0, allow_empty_first_page=True)
    • object_list
    • A list, tuple, QuerySet, or other sliceable object with a count()or len() method. For consistent pagination, QuerySets shouldbe ordered, e.g. with an clause or with a default ordering on themodel.

    Performance issues paginating large QuerySets

    If you're using a QuerySet with a very large number of items,requesting high page numbers might be slow on some databases, becausethe resulting LIMIT/OFFSET query needs to count the number ofOFFSET records which takes longer as the page number gets higher.

    • per_page
    • The maximum number of items to include on a page, not including orphans(see the orphans optional argument below).

    可选参数

    • orphans
    • Use this when you don't want to have a last page with very few items.If the last page would normally have a number of items less than or equalto orphans, then those items will be added to the previous page (whichbecomes the last page) instead of leaving the items on a page bythemselves. For example, with 23 items, per_page=10, andorphans=3, there will be two pages; the first page with 10 items andthe second (and last) page with 13 items. orphans defaults to zero,which means pages are never combined and the last page may have one item.
    • Whether or not the first page is allowed to be empty. If False andobject_list is empty, then an EmptyPage error will be raised.
    • Paginator.getpage(_number)[源代码]
    • Returns a Page object with the given 1-based index, while alsohandling out of range and invalid page numbers.

    If the page isn't a number, it returns the first page. If the page numberis negative or greater than the number of pages, it returns the last page.

    It raises an exception () only if you specifyPaginator(…, allow_empty_first_page=False) and the object_list isempty.

    • Paginator.page(number)[源代码]
    • Returns a Page object with the given 1-based index. Raises if the given page number doesn't exist.

    属性

    • Paginator.count
    • The total number of objects, across all pages.

    When determining the number of objects contained in object_list,Paginator will first try calling object_list.count(). Ifobject_list has no count() method, then Paginator willfallback to using len(object_list). This allows objects, such asDjango's QuerySet, to use a more efficient count() method whenavailable.

    • Paginator.num_pages

    • The total number of pages.

    • Paginator.page_range

    • A 1-based range iterator of page numbers, e.g. yielding [1, 2, 3, 4].
    • exception InvalidPage[源代码]
    • 当paginator对象试图访问无效页码时引发异常的基类。

    The Paginator.page() method raises an exception if the requested page isinvalid (i.e., not an integer) or contains no objects. Generally, it's enoughto catch the InvalidPage exception, but if you'd like more granularity,you can catch either of the following exceptions:

    • exception PageNotAnInteger

    • Raised when page() is given a value that isn't an integer.

    • exception EmptyPage

    • Raised when is given a valid value but no objects exist on thatpage.

    Both of the exceptions are subclasses of , so you can handlethem both with a simple except InvalidPage.

    你通常不会手动实例化Page对象 - 你会使用方法Paginator.page()。

    • class Page(object_list, number, paginator)[源代码]
    • A page acts like a sequence of Page.object_list when usinglen() or iterating it directly.

    • Returns True if there's a next page.

    • Page.has_previous()

    • Returns True if there's a previous page.

    • Returns True if there's a next or previous page.

    • Page.next_page_number()

    • Returns the next page number. Raises if next pagedoesn't exist.

    • Page.previous_page_number()[源代码]

    • Returns the previous page number. Raises InvalidPage if previouspage doesn't exist.

    • Page.start_index()

    • Returns the 1-based index of the first object on the page, relative to allof the objects in the paginator's list. For example, when paginating a listof 5 objects with 2 objects per page, the second page's would return 3.

    • Page.end_index()[源代码]

    • Returns the 1-based index of the last object on the page, relative to allof the objects in the paginator's list. For example, when paginating a listof 5 objects with 2 objects per page, the second page'send_index() would return 4.

    属性

    • Page.object_list

    • 此页上的对象列表。

    • Page.number

    • 此页的基于 1 的页码。

    • 关联的 Paginator 对象。