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Flask Paginate实现表格分页的使用示例

作者:微软技术分享

flask_paginate是Flask框架的一个分页扩展,用于处理分页相关的功能,本文就来介绍一下Flask Paginate实现表格分页的使用示例,感兴趣的可以了解一下

flask_paginate 是 Flask 框架的一个分页扩展,用于处理分页相关的功能。它可以帮助你在 Flask Web 应用程序中实现分页功能,让用户可以浏览大量数据的不同部分。本篇博文重点讲述在Web开发中,用paginate把所有数据进行分页展示,首先通过运用第三方库实现后端分页,然后再自己编写一个分页类实现。

flask_sqlalchemy

Flask-SQLAlchemy 是 Flask 框架的一个扩展,提供了对 SQL 数据库的集成支持。它基于 SQLAlchemy 构建,简化了在 Flask 应用中使用数据库的操作。

安装 Flask-SQLAlchemy

pip install Flask-SQLAlchemy

Flask-SQLAlchemy的使用很简单,如下是一些简单的用法;

from flask import Flask
from sqlalchemy import not_,or_,and_,desc
from flask_sqlalchemy import SQLAlchemy

app = Flask(__name__)

# url的格式为:数据库的协议://用户名:密码@ip地址:端口号(默认可以不写)/数据库名
app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///:memory:"

# 为了解决控制台的提示
app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False

# 创建数据库的操作对象
db = SQLAlchemy(app)

# 创建规则表
class RoleDB(db.Model):
    __tablename__ = "role"
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(16), unique=True)

    # 增加反查外键关联到UserDB
    users = db.relationship('UserDB', backref="role")

    # 当调用 Role.query.all() 会触发输出
    def __repr__(self):
        return "Role: %s | %s" % (self.id, self.name)

# 创建用户表
class UserDB(db.Model):
    __tablename__ = "user"
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(16), unique=True)
    email = db.Column(db.String(32), unique=True)
    password = db.Column(db.String(16))

    # 关联到RuleDB表中的ID上面
    role_id = db.Column(db.Integer, db.ForeignKey("role.id"))

    # 当调用 RoleDB.query.all() 会触发输出
    def __repr__(self):
        return "User: %s | %s | %s | %s" % (self.id, self.name, self.password, self.role_id)

@app.route('/')
def index():
    # 此处查询会走类内 __repr__ 输出
    print("查询所有用户数据: ", UserDB.query.all())
    print("查询所有规则数据: ", RoleDB.query.all())
    print("查询有多少个用户: ", UserDB.query.count())
    print("查询第一个用户: ", UserDB.query.first())

    # 查询过滤器
    print("查询第一条: ", UserDB.query.get(1))
    print("查询过滤器(类名+属性名): ", UserDB.query.filter(UserDB.id == 4).first())
    print("查询过滤器(属性名): ", UserDB.query.filter_by(id=4).first())

    # 查询名字结尾字符为g的所有数据 [开始/包含]
    print(UserDB.query.filter(UserDB.name.endswith("g")).all())
    print(UserDB.query.filter(UserDB.name.contains("g")).all())

    # 查询名字不等于wang的所有数据 [2种方式]
    print(UserDB.query.filter(not_(UserDB.name == "wang")).all())
    print(UserDB.query.filter(UserDB.name != "wang").all())

    #  查询 [名字和邮箱] 都以li开头的所有数据 [2种方式]
    print(UserDB.query.filter(and_(UserDB.name.startswith("li"),UserDB.email.startswith("li"))).all())
    print(UserDB.query.filter(UserDB.name.startswith("li"), UserDB.email.startswith("li")).all())

    # 查询password是 123456 或者 email 以 lyshark.com 结尾的所有数据
    print(UserDB.query.filter(or_(UserDB.password=='123456', UserDB.email.endswith('lyshark.com'))).all())

    # 查询id为 [1, 3, 5, 7, 9] 的用户列表
    print(UserDB.query.filter(UserDB.id.in_([1, 3, 5, 7, 9])).all())

    # 查询name为liu的角色数据:关系引用
    print(UserDB.query.filter_by(name="liu").first().role.name)

    # 查询所有用户数据 并以邮箱排序 [升序/降序]
    print("升序: ", UserDB.query.order_by("email").all())
    print("降序: ", UserDB.query.order_by(desc("email")).all())

    # 查询第2页的数据,每页只显示3条数据
    pages = UserDB.query.paginate(2,3,False)
    print("查询结果: {} 总页数: {} 当前页数: {}".format(pages.items,pages.pages,pages.page))

    # 完整查询调用写法
    ref = db.session.query(UserDB).filter(UserDB.name == "wang").all()
    print(ref)
    return "success"

if __name__ == "__main__":
    # 初始化数据表
    db.drop_all()
    db.create_all()

    # 插入两个规则记录
    role_admin = RoleDB(name="admin")
    db.session.add(role_admin)
    role_lyshark = RoleDB(name="lyshark")
    db.session.add(role_lyshark)
    db.session.commit()

    try:
        ua = UserDB(name='wang', email='wang@163.com', password='123456', role_id=role_admin.id)
        ub = UserDB(name='zhang', email='zhang@189.com', password='201512', role_id=role_lyshark.id)
        uc = UserDB(name='chen', email='chen@126.com', password='987654', role_id=role_lyshark.id)
        ud = UserDB(name='zhou', email='zhou@163.com', password='456789', role_id=role_admin.id)
        ue = UserDB(name='tang', email='tang@lyshark.com', password='158104', role_id=role_lyshark.id)
        uf = UserDB(name='wu', email='wu@gmail.com', password='5623514', role_id=role_lyshark.id)
        ug = UserDB(name='qian', email='qian@gmail.com', password='1543567', role_id=role_admin.id)
        uh = UserDB(name='liu', email='liu@lyshark.com', password='867322', role_id=role_admin.id)
        ui = UserDB(name='li', email='li@163.com', password='4526342', role_id=role_lyshark.id)
        uj = UserDB(name='sun', email='sun@163.com', password='235523', role_id=role_lyshark.id)
        db.session.add_all([ua, ub, uc, ud, ue, uf, ug, uh, ui, uj])
        db.session.commit()

    except Exception as e:
        # 插入失败自动回滚
        db.session.rollback()
        raise e

    app.run(debug=True)

flask_sqlalchemy 分页组件

Flask-SQLAlchemy 分页插件为 Flask 应用提供了便捷而强大的分页功能,通过 paginate() 方法返回的 Pagination 类对象,开发者能够轻松实现对大型数据集的分页展示。该插件基于 Flask-SQLAlchemy 扩展构建,简化了在 Flask 应用中进行数据库查询的分页操作。通过灵活的配置选项,开发者可以高效地管理和展示数据,提升用户体验,是构建数据驱动 Web 应用的重要利器。本文将深入介绍 Flask-SQLAlchemy 分页插件的基本使用方法以及常见配置选项,帮助开发者快速上手并充分发挥其强大的分页功能。

前端部分使用bootstrap实现分页组件,新建前端index.html文件,代码如下;

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <link rel="stylesheet" href="https://www.lyshark.com/javascript/bootstrap/5.1.3/css/bootstrap.min.css" rel="external nofollow"  rel="external nofollow"  rel="external nofollow" >
</head>
<body>
<div class="box box-primary">
    <div class="box-body table-responsive no-padding">
        <table class="table table-sm table-hover">
            <thread>
                <tr class="table-success">
                    <th>id</th>
                    <th>name</th>
                    <th>email</th>
                    <th>password</th>
                </tr>
            </thread>
            <tbody>
                {% for item in page_data.items %}
                    <tr class="table-primary">
                        <td>{{ item.id }}</td>
                        <td>{{ item.name }}</td>
                        <td>{{ item.email }}</td>
                        <td>{{ item.password }}</td>
                    </tr>
                {% endfor %}
            </tbody>
        </table>
    </div>

    <div class="box-footer clearfix">
        <nav class="d-flex justify-content-center" aria-label="Page navigation example">
            {% if page_data %}
                <ul class="pagination">
                    <li class="page-item"><a class="page-link" href="./1" rel="external nofollow" >首页</a></li>

                    {% if page_data.has_prev %}
                        <li class="page-item"><a class="page-link" href="{{ page_data.prev_num }}" rel="external nofollow" >上一页</a></li>
                    {% else %}
                        <li class="page-item" class="disabled"><a class="page-link" href="#" rel="external nofollow"  rel="external nofollow" >上一页</a></li>
                    {% endif %}
                    <!--
                    {% for item in page_data.iter_pages() %}
                        {% if item == page_data.page %}
                            <li class="page-item active"><a class="page-link" href="{{ item }}" rel="external nofollow"  rel="external nofollow" >{{ item }}</a></li>
                        {% else %}
                            <li class="page-item"><a class="page-link" href="{{ item }}" rel="external nofollow"  rel="external nofollow" >{{ item }}</a></li>
                        {% endif %}
                    {% endfor %}
                    -->

                    <!-- 当前页的页码/总页码 -->
                    <p>{{ page_data.page }}</p> / <p>{{ page_data.pages }}</p>

                    {% if page_data.has_next %}
                        <li class="page-item"><a class="page-link" href="{{ page_data.next_num  }}" rel="external nofollow" >下一页</a></li>
                    {% else %}
                        <li class="page-item" class="disabled"><a class="page-link" href="#" rel="external nofollow"  rel="external nofollow" >下一页</a></li>
                    {% endif %}
                    <li class="page-item"><a class="page-link" href="{{ page_data.pages }}" rel="external nofollow" >尾页</a></li>
                </ul>
            {% endif %}
        </nav>
    </div>
</div>
</body>
</html>

使用组件内的过滤器分页是非常简单的一件事,只需要调用参数后返回,后端app.py代码如下;

from flask import Flask,render_template,request
from flask_sqlalchemy import SQLAlchemy

app = Flask(__name__, template_folder="./tempate",static_folder="./tempate")

app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///database.db"

# 设置每次请求结束后会自动提交数据库的改动
app.config['SQLALCHEMY_COMMIT_ON_TEARDOWN'] = True
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True

# 查询时显示原始SQL语句
app.config['SQLALCHEMY_ECHO'] = False

# 创建数据库的操作对象
db = SQLAlchemy(app)

# 创建用户表
class UserDB(db.Model):
    __tablename__="user"
    id = db.Column(db.Integer,primary_key=True)
    name = db.Column(db.String(32))
    email = db.Column(db.String(32))
    password = db.Column(db.String(32))

    def __init__(self,name,email,password):
        self.name = name
        self.email = email
        self.password = password

    def __repr_(self):
        return 'User %s'%self.name

@app.route("/")
def index():
    return "<script>window.location.href='./page/1'</script>"

@app.route("/page/<int:page_number>")
def page(page_number=None):
    if page_number is None:
        page_number = 1

    page = db.session.query(UserDB).paginate(page=page_number,per_page=10,max_per_page=15)
    return render_template("index.html", page_data = page)

if __name__ == "__main__":
    # 初始化数据表
    db.drop_all()
    db.create_all()
    try:
        ua = UserDB(name='wang', email='wang@163.com', password='123456')
        ub = UserDB(name='zhang', email='zhang@189.com', password='201512')
        uc = UserDB(name='chen', email='chen@126.com', password='987654')
        ud = UserDB(name='zhou', email='zhou@163.com', password='456789')
        ue = UserDB(name='tang', email='tang@lyshark.com', password='158104')
        uf = UserDB(name='wu', email='wu@gmail.com', password='5623514')
        ug = UserDB(name='qian', email='qian@gmail.com', password='1543567')
        uh = UserDB(name='liu', email='liu@lyshark.com', password='867322')
        ui = UserDB(name='li', email='li@163.com', password='4526342')
        uj = UserDB(name='sun', email='sun@163.com', password='235523')
        db.session.add_all([ua, ub, uc, ud, ue, uf, ug, uh, ui, uj,uj,uj,uj,uj,uj,uj,uj,uj])
        db.session.commit()

    except Exception as e:
        # 插入失败自动回滚
        db.session.rollback()
        raise e
    app.run(debug=True)

flask_paginate 分页组件

Flask-Paginate 是 Flask 框架中的一个重要插件,为开发者提供了便捷而灵活的分页解决方案。通过结合 Flask 官方的分页部件,这个插件能够轻松地实现对大量数据的分页展示,为用户提供更友好的浏览体验。本文将深入介绍 Flask-Paginate 的核心功能、使用方法以及与数据库查询的协同操作,帮助开发者更好地利用这一工具来优化 Web 应用的分页展示。

前端部分使用bootstrap实现分页组件,新建前端index.html文件,代码如下;

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <link rel="stylesheet" href="https://www.lyshark.com/javascript/bootstrap/5.1.3/css/bootstrap.min.css" rel="external nofollow"  rel="external nofollow"  rel="external nofollow" >
</head>
<body>
<table class="table table-sm table-hover">
    <thead>
        <tr class="table-success">
            <th>序号</th>
            <th>用户ID</th>
            <th>用户名称</th>
            <th>用户邮箱</th>
            <th>用户密码</th>
        </tr>
    </thead>
    <tbody>
        {% for article in articles %}
            <tr class="table-primary">
                <td>{{ loop.index }}</td>
                <td>{{ article.id }}</td>
                <td>{{ article.name }}</td>
                <td>{{ article.email }}</td>
                <td>{{ article.password }}</td>
            </tr>
        {% endfor %}
    </tbody>
</table>
<nav class="d-flex justify-content-center" aria-label="Page navigation example">
  <ul class="pagination">
    <li class="page-item"><a class="page-link" href="./page=1" rel="external nofollow"  rel="external nofollow" >首页</a></li>
      {% if pagination.has_prev %}
           <li class="page-item"><a class="page-link" href="./page={{ prve_num }}" rel="external nofollow" >上一页</a></li>
      {% endif %}

        <!--获取当前列表,并全部填充到这里-->
        {% for item in pageRange %}
            <!--判断如果是当前页则直接标号为蓝色高亮-->
            {% if item == currentPage %}
                <li class="page-item active"><a class="page-link" href="./page={{ item }}" rel="external nofollow"  rel="external nofollow" >{{ item }}</a></li>
            <!--否则的话,就直接接收参数填充-->
            {% else %}
                <li class="page-item"><a class="page-link" href="./page={{ item }}" rel="external nofollow"  rel="external nofollow" >{{ item }}</a></li>
            {% endif %}
        {% endfor %}

      {% if next_end %}
          <li class="page-item"><a class="page-link" href="./page={{ next_num }}" rel="external nofollow" >下一页</a></li>
      {% endif %}
    <li class="page-item"><a class="page-link" href="./page={{ PageCount }}" rel="external nofollow" >尾页</a></li>
  </ul>
</nav>

  <div style="text-align: center;" class="alert alert-dark">
   统计: {{ pagination.page }}/{{ PageCount }} 共查询到:{{ pagination.total }} 条数据 页码列表:{{ pageRange }}
  </div>
</body>
</html>

后端就是对请求的响应,前端用户通过GET方式访问,后端获得用户页面数,查询后动态展示出来即可。

from flask import Flask,render_template,request
from flask_sqlalchemy import SQLAlchemy
from flask_paginate import Pagination,get_page_parameter
import math

app = Flask(__name__, template_folder="./tempate",static_folder="./tempate")

# url的格式为:数据库的协议://用户名:密码@ip地址:端口号(默认可以不写)/数据库名
app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///database.db"

# 设置每次请求结束后会自动提交数据库的改动
app.config['SQLALCHEMY_COMMIT_ON_TEARDOWN'] = True
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True

# 查询时显示原始SQL语句
app.config['SQLALCHEMY_ECHO'] = False

# 创建数据库的操作对象
db = SQLAlchemy(app)

# 创建用户表
class UserDB(db.Model):
    __tablename__="user"
    id = db.Column(db.Integer,primary_key=True)
    name = db.Column(db.String(32))
    email = db.Column(db.String(32))
    password = db.Column(db.String(32))

    def __init__(self,name,email,password):
        self.name = name
        self.email = email
        self.password = password

    def __repr_(self):
        return 'User %s'%self.name

@app.route("/")
def index():
    return """<script>window.location.href="./page=1" rel="external nofollow"  rel="external nofollow" </script>"""

@app.route("/page=<int:id>")
def GetPages(id):
    # 默认每页显示10个元素
    PER_PAGE = 10

    total = db.session.query(UserDB).count()
    print("总记录 {} 条".format(total))

    currentPage = request.args.get(get_page_parameter(),type=int,default=int(id))
    print("当前页码ID为 {}".format(currentPage))

    start = (currentPage-1)*PER_PAGE   # 分页起始位置
    end = start+PER_PAGE               # 分页结束位置
    print("起始位置 {} 结束位置 {}".format(start,end))

    prev_num = int(currentPage)-1
    next_num = int(currentPage)+1
    print("上一页页码 {} 下一页页码 {}".format(prev_num,next_num))

    # 计算出需要切割的页数
    page_count = math.ceil(total/PER_PAGE)
    print("切割页数 {}".format(page_count))

    pagination = Pagination(page=currentPage,total=total)

    # 执行数据库切片
    articles = db.session.query(UserDB).slice(start,end)

    # 判断,如果next_end大于总数说明到最后了
    if currentPage>=math.ceil(total/PER_PAGE):
        # 那么我们就将next_end设置为0,前端就不执行显示了
        next_end=0
    else:
        next_end=1

    # -------------------------------------------------
    # 此页面是扩展部分,用于生成当前页码,并填充到前端

    # 如果总页数小于15则一次性生成页码即可
    if page_count < 15:
        pageRange = range(1,page_count+1)

    # 总页数大于15则需要分情况生成
    elif page_count > 15:
        # 说明是第一页
        if currentPage-5 < 1:
            pageRange = range(1,11)
        # 说明是最后一页
        elif currentPage+5 > page_count:
            pageRange = range(currentPage-5,page_count)
        # 说明是中间页
        else:
            pageRange = range(currentPage-5,currentPage+5)

    # 如果都不是则返回总数
    else:
        pageRange = page_count

    print("生成的当前页码: {}".format(pageRange))

    context = {
        'pagination': pagination,
        'articles': articles,
        'prve_num': prev_num,
        'next_num': next_num,
        'PageCount': page_count,
        'pageRange': pageRange,
        'next_end': next_end,
        "currentPage": currentPage
    }
    return render_template('index.html',**context)

if __name__ == "__main__":
    db.drop_all()
    db.create_all()
    try:
        ua = UserDB(name='wang', email='wang@163.com', password='123456')
        ub = UserDB(name='zhang', email='zhang@189.com', password='201512')
        uc = UserDB(name='chen', email='chen@126.com', password='987654')
        ud = UserDB(name='zhou', email='zhou@163.com', password='456789')
        ue = UserDB(name='tang', email='tang@lyshark.com', password='158104')
        uf = UserDB(name='wu', email='wu@gmail.com', password='5623514')
        ug = UserDB(name='qian', email='qian@gmail.com', password='1543567')
        uh = UserDB(name='liu', email='liu@lyshark.com', password='867322')
        ui = UserDB(name='li', email='li@163.com', password='4526342')
        uj = UserDB(name='sun', email='sun@163.com', password='235523')
        db.session.add_all([ua, ub, uc, ud, ue, uf, ug, uh, ui, uj,uj,uj,uj,uj,uj,uj,uj,uj])
        db.session.commit()

    except Exception as e:
        # 插入失败自动回滚
        db.session.rollback()
        raise e
    app.run(debug=True)

Pagination 自写分页器

前端部分使用bootstrap实现分页组件,新建前端index.html文件,代码如下;

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <link rel="stylesheet" href="https://www.lyshark.com/javascript/bootstrap/5.1.3/css/bootstrap.min.css" rel="external nofollow"  rel="external nofollow"  rel="external nofollow" >
</head>
<body>
    <table class="table table-sm table-hover">
        <thead>
            <tr class="table-success">
                <th>用户ID</th>
                <th>用户名称</th>
                <th>用户邮箱</th>
                <th>用户密码</th>
            </tr>
        </thead>
        <tbody>
            {% for article in articles %}
                <tr class="table-primary">
                    <td>{{ article.id }}</td>
                    <td>{{ article.name }}</td>
                    <td>{{ article.email }}</td>
                    <td>{{ article.password }}</td>
                </tr>
            {% endfor %}
        </tbody>
    </table>

    <!--输出页码范围-->
    <nav class="d-flex justify-content-center" aria-label="Page navigation example">
         <ul class="pagination">
            {{ html|safe }}
        </ul>
    </nav>
</body>
</html>

首先需要创建一个pager.py文件,里面包含一个Pagination分页类部件。

import copy
from urllib.parse import urlencode

class Pagination(object):
    def __init__(self,current_page,total_count,base_url,params,per_page_count=10,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
        params = copy.deepcopy(params)
        # params._mutable = True
        get_dict = params.to_dict()
        # 包含当前列表页面所有的搜/索条件
        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 = []
        # 首页
        self.params['page'] = 1
        first_page = '<li class="page-item"><a class="page-link" href="%s?%s" rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  rel="external nofollow" >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="page-item" class="disabled"><a class="page-link" \
            href="%s?%s" rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  aria-label="Previous">上一页</span></a></li>' % (self.base_url, urlencode(self.params))
        else:
            pervious_page = '<li class="page-item"><a class="page-link" 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="page-item active" class="active"><a class="page-link" \
                href="%s?%s" rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  rel="external nofollow" >%s</a></li>' % (self.base_url,urlencode(self.params), i,)
            else:
                temp = '<li  class="page-item"><a class="page-link" \
                href="%s?%s" rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  rel="external nofollow" >%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="page-item" class="disabled"><a class="page-link" \
            href = "%s?%s" aria-label = "Next">下一页</span></a></li >' % (self.base_url, urlencode(self.params))
        else:
            next_page = '<li class="page-item"><a class="page-link" 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 class="page-item"><a class="page-link" href="%s?%s" rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  rel="external nofollow"  rel="external nofollow" >尾页</a></li>' % (self.base_url, urlencode(self.params),)
        page_html_list.append(last_page)
        return ''.join(page_html_list)

主函数main.py则直接import Pagination导入分页类,然后调用Pagination函数即可实现分页了。

from flask import Flask,render_template,request
from flask_sqlalchemy import SQLAlchemy
from pager import Pagination

app = Flask(__name__, template_folder="./tempate",static_folder="./tempate")

app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///database.db"

# 设置每次请求结束后会自动提交数据库的改动
app.config['SQLALCHEMY_COMMIT_ON_TEARDOWN'] = True
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True

# 查询时显示原始SQL语句
app.config['SQLALCHEMY_ECHO'] = False

# 创建数据库的操作对象
db = SQLAlchemy(app)

# 创建用户表
class UserDB(db.Model):
    __tablename__="user"
    id = db.Column(db.Integer,primary_key=True)
    name = db.Column(db.String(32))
    email = db.Column(db.String(32))
    password = db.Column(db.String(32))

    def __init__(self,name,email,password):
        self.name = name
        self.email = email
        self.password = password

    def __repr_(self):
        return 'User %s'%self.name

@app.route("/")
def index():
    total = db.session.query(UserDB).count()
    print("查询总记录数: {}".format(total))

    page_number = request.args.get("page", 1)
    print("当前传入页码: {}".format(page_number))

    # 分页类 [ Pagination(传入页码/总记录数/分页URL前缀/传入数据params/每页显示数/最大显示页码 )]
    Page = Pagination(page_number, total, request.path, request.args, per_page_count=10, max_pager_count=15)

    # 对数据切片
    index = db.session.query(UserDB)[Page.start:Page.end]
    print("页面切片: {}".format(index))

    # 渲染页面
    html = Page.page_html()
    print("渲染页码页面: {}".format(html))

    return render_template("index.html",articles=index,html=html)

if __name__ == "__main__":
    # 初始化数据表
    db.drop_all()
    db.create_all()
    try:
        ua = UserDB(name='wang', email='wang@163.com', password='123456')
        ub = UserDB(name='zhang', email='zhang@189.com', password='201512')
        uc = UserDB(name='chen', email='chen@126.com', password='987654')
        ud = UserDB(name='zhou', email='zhou@163.com', password='456789')
        ue = UserDB(name='tang', email='tang@lyshark.com', password='158104')
        uf = UserDB(name='wu', email='wu@gmail.com', password='5623514')
        ug = UserDB(name='qian', email='qian@gmail.com', password='1543567')
        uh = UserDB(name='liu', email='liu@lyshark.com', password='867322')
        ui = UserDB(name='li', email='li@163.com', password='4526342')
        uj = UserDB(name='sun', email='sun@163.com', password='235523')
        db.session.add_all([ua, ub, uc, ud, ue, uf, ug, uh, ui, uj,uj,uj,uj,uj,uj,uj,uj,uj])
        db.session.commit()

    except Exception as e:
        # 插入失败自动回滚
        db.session.rollback()
        raise e
    app.run(debug=True)

到此这篇关于Flask Paginate实现表格分页的使用示例的文章就介绍到这了,更多相关Flask Paginate表格分页内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家!

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