Django 08

sweetalert弹窗

  • 下载sweetalert并存放在Django项目中的静态文件夹中 https://github.com/MrBigBlake/bootstrap-sweetalert
  • 选择想要的弹窗样式直接copy过来快乐的改呀改https://lipis.github.io/bootstrap-sweetalert/
  • 如何查找到for循环中的a标签: 可以添加一个类属性
  • 通过DOM操作直接移除页面上已经被删除的数据标签
# 通过sweetalert实现删除数据时触发弹窗, 确认是否删除
def home(request):
    user_queryset = models.User.objects.all()
    if request.is_ajax():
        back_dic = {'code': 1000, 'msg': ''}
        print(request.POST)
        delete_id = int(request.POST.get('delete_id')[0])
        time.sleep(2)
        models.User.objects.filter(pk=delete_id).delete()
        back_dic['msg'] = 'Data has been deleted'
        return JsonResponse(back_dic)
    return render(request, 'home.html', locals())
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    {% load  static %}
    <script src="{% static 'JQuery-3.4.1/JQuery.js' %}"></script>
    <script src="{% static 'bootstrap-3.3.7-dist/js/bootstrap.min.js' %}"></script>
    <script src="{% static 'bootstrap-sweetalert-master/dist/sweetalert.min.js' %}"></script>
    <link rel="stylesheet" href="{% static 'bootstrap-sweetalert-master/dist/sweetalert.css' %}">
    <link rel="stylesheet" href="{% static 'bootstrap-3.3.7-dist/css/bootstrap.min.css' %}">
</head>
<body>
<div class="container">
    <div class="row"></div>
    <div class="col-md-8 col-md-offset-2">
        <h1 class="text-center">User Info</h1>
        <table class="table table-hover table-bordered table-striped">
            <thead>
            <tr>
                <th>NO.</th>
                <th>Username</th>
                <th>Age</th>
                <th>Gender</th>
                <th class="text-center">Actions</th>
            </tr>
            </thead>
            <tbody>
            {% for user in user_queryset %}
                <tr>
                    <td>{{ forloop.counter }}</td>
                    <td>{{ user.username }} </td>
                    <td>{{ user.age }} </td>
                    <td>{{ user.get_gender_display }} </td>
                    <td class="text-center">
                        <a href="#" class="btn btn-primary btn-sm">Edit</a>
                        {#给a标签加一个cancel类以便定位到该标签#}
                        <a href="#" class="btn btn-danger btn-sm cancel" id={{ user.pk }}>Delete</a>
                    </td>
                </tr>
            {% endfor %}
            </tbody>
        </table>
    </div>
</div>

<script>
    $(".cancel").click(function () {
        let $btn = $(this);
        swal({
                title: "Are you sure?",
                text: "You will not be able to recover this imaginary file!",
                type: "warning",
                showCancelButton: true,
                confirmButtonClass: "btn-danger",
                confirmButtonText: "Yes, delete it!",
                cancelButtonText: "No, cancel plx!",
                closeOnConfirm: false,
                closeOnCancel: false,
                showLoaderOnConfirm: true
            },
            function (isConfirm) {
                if (isConfirm) {
                    $.ajax({
                        url: "",
                        type: "post",
                        data: {"delete_id": $btn.attr('id')},
                        success: function (data) {
                            if (data.code==1000) {
                                swal("Deleted!", "Data has been deleted.", "success");
                                {#通过DOM操作直接将删除的标签移除#}
                                $btn.parent().parent().remove()
                            } else {
                                swal("Error", "Unknown error", "warning");
                            }
                        }
                    });
                } else {
                    swal("Cancelled", "Data delete has been cancelled :)", "error");
                }
            })
    });
</script>
</body>
</html>

bulk-create

  • 用于向数据库中批量添加数据
  • 先将数据对象都添加到列表中, 然后将该列表传给bulk_create方法
# 这样向数据库添加大量数据速度非常慢, 甚至会导致程序崩溃 
for i in range(10000):
    models.Book.objects.create(title=f'book-{i}')
    
# 使用bulk_create方法可快速向数据库中添加大量数据对象    
lis = []
for i in range(10000):
    obj = models.Book(title=f'book-{i}')
    lis.append(obj)
models.Book.objects.bulk_create(lis) 

自定义分页器

  • queryset对象支持切片操作
  • 可以直接向html文件发送html代码(字符串格式)
# 实现简单的分页展示效果
def index(request):
    # 分页器一次展示的页数为 page_controller * 2 + 1
    page_controller = 3
    if page_controller < 1:
        page_controller = 1
        
    # 数据库图书个数
    book_num = models.Book.objects.all().count()
    per_page_num = 5
    
    # 判断一共有多少页
    page_num, more = divmod(book_num, per_page_num)
    if more:
        page_num += 1

    # 获取当前页数, 设置默认值为1
    page_init = int(request.GET.get('page', 1))
    page = page_init

    # 防止分页器末尾超出总页数
    if page_init > page_num - page_controller:
        page = page_num - page_controller

    # 防止分页器开头出现0或负数页
    if page_init < page_controller + 1:
        page = page_controller + 1

    # 切片操作的起始和结束位置
    page_start = (page_init - 1) * per_page_num
    page_end = page_init * per_page_num

    # 切片获取当前页数对应的图书数据
    book_queryset = models.Book.objects.all()[page_start: page_end]

    # 直接向html文件发送html代码
    html = ''
    for i in range(page - page_controller, page + page_controller + 1):

        # 当前页标签高亮
        if i == page_init:
            html += f'<li class="active"><a href="?page={i}">{i}</a></li>'
        else:
            html += f'<li><a href="?page={i}">{i}</a></li>'

    return render(request, 'index.html', locals())
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    {% load static %}
    <script src="{% static 'JQuery-3.4.1/JQuery.js' %}"></script>
    <script src="{% static 'bootstrap-3.3.7-dist/js/bootstrap.min.js' %}"></script>
    <link rel="stylesheet" href="{% static 'bootstrap-3.3.7-dist/css/bootstrap.min.css' %}">
</head>
<body>
<div class="container">
    <div class="row">
        <div class="col-md-6 col-md-offset-3">
            <h1 class="text-center">Book List</h1>
            <table class="table table-striped table-bordered table-hover">
                <thead>
                <tr>
                    <th>NO.</th>
                    <th>Book Title</th>
                </tr>
                </thead>
                <tbody>
                {% for book in book_queryset %}
                    <tr>
                        <td>{{ book.pk }}</td>
                        <td>{{ book.title }}</td>
                    </tr>
                {% endfor %}
                </tbody>
            </table>
        <div class="text-center">
            <nav aria-label="Page navigation">
                <ul class="pagination">
                        {{ html|safe }}
                </ul>
            </nav>
            </div>
        </div>
    </div>
</div>
</body>
</html>
  • 第三方分页器的使用
  • 在app文件夹或者总项目文件夹下, 新建utils文件夹, 将下面分页文件放到utils文件下
  • 两个参数: current_pageall_count
  • 将html代码字符串封装到了 pagination_obj.page_html
# Pagination.py
class Pagination(object):
    def __init__(self,current_page,all_count,per_page_num=10,pager_count=5):
        """
        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)
def index(request):
	book_queryset = models.Book.objects.all()
    # 两个参数, 当前页和数据数量
    current_page = request.GET.get('page', 1)
    all_count = book_queryset.count()
    # 实例化出分页器对象
    pagination_obj = Pagination(current_page=current_page, all_count=all_count)
    # 切片获取当前页的数据
    page_queryset = book_queryset[pagination_obj.start:pagination_obj.end]
    return render(request, 'index.html', locals())
<table class="table table-striped table-bordered table-hover">
                <thead>
                <tr>
                    <th>NO.</th>
                    <th>Book Title</th>
                </tr>
                </thead>
                <tbody>
                {% for book in page_queryset %}
                    <tr>
                        <td>{{ book.pk }}</td>
                        <td>{{ book.title }}</td>
                    </tr>
                {% endfor %}
                </tbody>
            </table>
        <div class="text-center">
            {{ pagination_obj.page_html|safe }}
            </div>
        </div>
posted @ 2019-12-02 21:26  MrBigB  阅读(108)  评论(0编辑  收藏  举报