一、知识点:

表单创建
数据库操作
一对多关系演练

二、实现步骤:

创建数据库配置信息,定义模型类
创建数据库表,添加测试数据
编写html页面,展示数据
添加数据
删除书籍,删除作者

三、创建数据库连接信息,定义模型

在这里插入图片描述

from flask import Flask, render_template, redirect, url_for, flash, request
from flask_sqlalchemy import SQLAlchemy
from flask_wtf.csrf import CSRFProtectapp = Flask(__name__)#开启csrf保护
CSRFProtect(app)#设置数据库配置信息
app.config['SQLALCHEMY_DATABASE_URI'] = "mysql+pymysql://root:123456@127.0.0.1:3306/library2"
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False #压制警告信息#创建SQLAlchemy对象,关联app
db = SQLAlchemy(app)#设置密码
app.config['SECRET_KEY'] = "jfkdjfkdkjf"#编写模型类
#作者(一方)
class Author(db.Model):__tablename__ = 'authors'id = db.Column(db.Integer,primary_key=True)name = db.Column(db.String(64),unique=True)#关系属性和反向引用books = db.relationship('Book',backref='author')#书籍(多方)
class Book(db.Model):__tablename__ = 'books'id = db.Column(db.Integer,primary_key=True)name = db.Column(db.String(64),unique=True)#外键author_id = db.Column(db.Integer,db.ForeignKey('authors.id')) #或者是, Author.id#添加书籍
@app.route('/add_book', methods=['POST'])
def add_book():"""思路分析:1.获取参数2.校验参数3.通过作者名称,查询作者对象4.判断作者,判断书籍,进行添加5.重定向展示页:return:"""# 1.获取参数author_name = request.form.get("author")book_name = request.form.get("book")# 2.校验参数if not all([author_name,book_name]):return "作者或者书籍为空"# 3.通过作者名称,查询作者对象author = Author.query.filter(Author.name == author_name).first()  # 有金庸# 4.判断作者,判断书籍,进行添加# 判断作者是否存在if author:# 通过书籍名称,查询书籍对象 数据库,古龙写了 天龙八部book = Book.query.filter(Book.name == book_name, Book.author_id == author.id).first()# 判断书籍是否存在if book:flash('该作者有该书籍')else:# 创建书籍对象,添加到数据库book = Book(name=book_name, author_id=author.id)db.session.add(book)db.session.commit()else:# 创建作者添加到数据库author = Author(name=author_name)db.session.add(author)db.session.commit()# 创建书籍添加到数据库book = Book(name=book_name, author_id=author.id)db.session.add(book)db.session.commit()# 5.重定向展示页return redirect(url_for('show_page'))#删除书籍
@app.route('/delete_book/<int:book_id>')
def delete_book(book_id):#1.根据编号获取书籍对象book = Book.query.get(book_id)#2.删除书籍db.session.delete(book)db.session.commit()#3.重定向页面展示return redirect(url_for('show_page'))#删除作者
@app.route('/delete_author/<int:author_id>')
def delete_author(author_id):#1.通过编号获取作者对象author = Author.query.get(author_id)#2.删除作者书籍for book in author.books:db.session.delete(book)#3.删除作者对象db.session.delete(author)db.session.commit()#4.重定向展示页面return redirect(url_for('show_page'))if __name__ == '__main__':app.run(debug=True)

myCode

from flask import Flask,render_template,flash,request
from flask_sqlalchemy import SQLAlchemyfrom flask_wtf import FlaskForm
from wtforms import StringField,SubmitField
from wtforms.validators import DataRequiredapp = Flask(__name__)# 数据库配置：数据库地址、关闭自动跟踪修改
app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://root:root@127.0.0.1/flask_books'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
app.secret_key = 'Zep03'# 创建数据库对象
db = SQLAlchemy(app)'''
1. 配置数据库a.导入SQLAlchemy扩展b.创建db对象，并配置参数c.通过mysql终端创建数据库
2. 添加书和作者的模型a.模型要继承db.Modelb.__tablaname__:定义表名c.db.Column:定义字段名d.db.relationship: 关系引用
3. 添加数据
4. 使用模板显示数据库查询的数据a.查询所有的作者信息，将信息传递给模板b.模板中按照格式，一次for循环作者和书籍即可（作者获取书籍，用的是关系引用）
5. 使用WTF显示表单a.自定义表单类b.模板中显示c.设置secret_key/解决编码问题/csrf_token
6. 实现相关的增删逻辑a.增加数据'''# 定义书和作者模型# 作者模型
class Author(db.Model):# 表名__tablename__ = 'authors'# 字段名id = db.Column(db.Integer,primary_key=True) #作者idname = db.Column(db.String(16),unique=True) #作者名name# 关系引用# books是给Author自己用的,author是给Book模型用的books = db.relationship('Book',backref='author')def __refr__(self):return 'Author: %s ' % self.name# 书籍模型
class Book(db.Model):# 表名__tablename__ = 'books'# 字段名id = db.Column(db.Integer, primary_key=True)  # 书籍的idname = db.Column(db.String(16), unique=True)  # 书籍名nameauthor_id = db.Column(db.Integer,db.ForeignKey('authors.id'))def __refr__(self):return 'Book: %s %s ' % self.name,self.author_id# 自定义表单类
class AuthorForm(FlaskForm):author = StringField('作者',validators=[DataRequired()])book = StringField('书籍',validators=[DataRequired()])submit = SubmitField('提交')@app.route('/',methods=['GET','POST'])
def index():# 创建自定义的表单类author_form = AuthorForm()'''验证逻辑:1. 调用WTF的函数实现验证2. 验证通过获取数据3. 判断作者是否存在4. 如果作者存在，判断书籍是否存在，没有重复书籍就添加书籍信息；如果重复就提示错误5. 如果作者不存在，添加作者和书籍6. 验证不通过就提示错误'''# 1. 调用WTF的函数实现验证if author_form.validate_on_submit():# 2. 验证通过获取数据author_name =  author_form.author.databook_name = author_form.book.data# 3. 判断作者是否存在:到数据库中查询author = Author.query.filter_by(name = author_name).first()# 4. 如果作者存在，if author:# 判断书籍是否存在，book = Book.query.filter_by(name = book_name).first()# 如果重复就提示错误if book:flash('已存在同名书籍！')# 没有重复书籍就添加书籍信息；else:try:new_book = Book(name = book_name,author_id=author.id)db.session.add(new_book)db.session.commit()except Exception as e:print(e)flash('添加书籍失败！')db.session.rollback() # 添加失败要进行回滚操作！# 5. 如果作者不存在,添加作者和书籍else:try:new_author = Author(name = author_name)db.session.add(new_author)db.session.commit()new_book = Book(name = book_name,author_id = new_author.id)db.session.add(new_book)db.session.commit()except Exception as e:print(e)flash('添加作者和书籍失败！')db.session.rollback()else:# 6. 验证不通过就提示错误if request.method == 'POST':flash('参数不全')# {查询所有的作者信息，让信息传递给模板 }authors = Author.query.all()return render_template('books.html',authors= authors,form = author_form)if __name__ == '__main__':db.drop_all()db.create_all()# 生成数据au1 = Author(name='老王')au2 = Author(name='老尹')au3 = Author(name='老刘')# 把数据提交给用户会话db.session.add_all([au1, au2, au3])# 提交会话db.session.commit()bk1 = Book(name='老王回忆录', author_id=au1.id)bk2 = Book(name='我读书少，你别骗我', author_id=au1.id)bk3 = Book(name='如何才能让自己更骚', author_id=au2.id)bk4 = Book(name='怎样征服美丽少女', author_id=au3.id)bk5 = Book(name='如何征服英俊少男', author_id=au3.id)# 把数据提交给用户会话db.session.add_all([bk1, bk2, bk3, bk4, bk5])# 提交会话db.session.commit()app.run(debug=True)

在这里插入图片描述

四、创建表,添加测试数据

if __name__ == '__main__':#为了演示方便,先删除所有表,再创建db.drop_all()db.create_all()#添加测试数据库# 生成数据au1 = Author(name='老王')au2 = Author(name='老尹')au3 = Author(name='老刘')# 把数据提交给用户会话db.session.add_all([au1, au2, au3])# 提交会话db.session.commit()bk1 = Book(name='老王回忆录', author_id=au1.id)bk2 = Book(name='我读书少，你别骗我', author_id=au1.id)bk3 = Book(name='如何才能让自己更骚', author_id=au2.id)bk4 = Book(name='怎样征服美丽少女', author_id=au3.id)bk5 = Book(name='如何征服英俊少男', author_id=au3.id)# 把数据提交给用户会话db.session.add_all([bk1, bk2, bk3, bk4, bk5])# 提交会话db.session.commit()app.run(debug=True)

五、数据显示&表单添加

后端代码:

#展示页面
@app.route('/')
def show_page():#查询数据库authors = Author.query.all()# 渲染到页面return render_template('library.html',authors=authors)

前端代码
创建文件 library.html ,编写以下代码:

<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>Title</title>
</head>
<body>{#注册表单#}<form action="/add_book" method="post">{# 设置隐藏的csrf_token #}<input type="hidden" name="csrf_token" value="{{ csrf_token() }}"><p><label>作者</label><input type="text" name="author"><br></p><p><label>书籍</label><input type="text" name="book"><br></p><p><input type="submit" value="添加"></p>{% for message in get_flashed_messages() %}<span style="color: red">{{ message }}</span>{% endfor %}</form><hr>{# 书籍展示 #}<h2>书籍展示</h2><ul>{% for author in authors %}<li>作者: {{ author.name }} <a href="{{ url_for('delete_author',author_id=author.id) }}">删除</a></li><br><ul>{% for book in author.books %}<li>书籍: {{ book.name }} <a href="{{ url_for('delete_book',book_id=book.id) }}">删除</a></li><br>{% endfor %}</ul>{% endfor %}</ul>
</body>
</html>

六、添加数据

添加书籍

@app.route('/add_book', methods=['POST'])
def add_book():"""思路分析:1.获取参数2.校验参数3.通过作者名称,查询作者对象4.判断作者,判断书籍,进行添加5.重定向展示页:return:"""# 1.获取参数author_name = request.form.get("author")book_name = request.form.get("book")# 2.校验参数if not all([author_name,book_name]):return "作者或者书籍为空"# 3.通过作者名称,查询作者对象author = Author.query.filter(Author.name == author_name).first()  # 有金庸# 4.判断作者,判断书籍,进行添加# 判断作者是否存在if author:# 通过书籍名称,查询书籍对象 数据库,古龙写了 天龙八部book = Book.query.filter(Book.name == book_name, Book.author_id == author.id).first()# 判断书籍是否存在if book:flash('该作者有该书籍')else:# 创建书籍对象,添加到数据库book = Book(name=book_name, author_id=author.id)db.session.add(book)db.session.commit()else:# 创建作者添加到数据库author = Author(name=author_name)db.session.add(author)db.session.commit()# 创建书籍添加到数据库book = Book(name=book_name, author_id=author.id)db.session.add(book)db.session.commit()# 5.重定向展示页return redirect(url_for('show_page'))

七、删除数据

删除书籍

#删除书籍
@app.route('/delete_book/<int:book_id>')
def delete_book(book_id):#1.根据编号获取书籍对象book = Book.query.get(book_id)#2.删除书籍db.session.delete(book)db.session.commit()#3.重定向页面展示return redirect(url_for('show_page'))

删除作者

#删除作者
@app.route('/delete_author/<int:author_id>')
def delete_author(author_id):#1.通过编号获取作者对象author = Author.query.get(author_id)#2.删除作者书籍for book in author.books:db.session.delete(book)#3.删除作者对象db.session.delete(author)db.session.commit()#4.重定向展示页面return redirect(url_for('show_page'))

八、案例完整代码

在这里插入图片描述

Flask_books_project.py文件

from flask import Flask,render_template,flash,request,redirect,url_for
from flask_sqlalchemy import SQLAlchemyfrom flask_wtf import FlaskForm
from wtforms import StringField,SubmitField
from wtforms.validators import DataRequiredapp = Flask(__name__)# 数据库配置：数据库地址、关闭自动跟踪修改
app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://root:root@127.0.0.1/flask_books'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
app.secret_key = 'Zep03'# 创建数据库对象
db = SQLAlchemy(app)'''
1. 配置数据库a.导入SQLAlchemy扩展b.创建db对象，并配置参数c.通过mysql终端创建数据库
2. 添加书和作者的模型a.模型要继承db.Modelb.__tablaname__:定义表名c.db.Column:定义字段名d.db.relationship: 关系引用
3. 添加数据
4. 使用模板显示数据库查询的数据a.查询所有的作者信息，将信息传递给模板b.模板中按照格式，一次for循环作者和书籍即可（作者获取书籍，用的是关系引用）
5. 使用WTF显示表单a.自定义表单类b.模板中显示c.设置secret_key/解决编码问题/csrf_token
6. 实现相关的增删逻辑a.增加数据b.删除书籍——》网页中删除——》点击需要发送书籍的ID给删除书籍的路由——》路由需要接收参数url_for的使用 / for else的使用 / redirect的使用c.删除作者'''# 定义书和作者模型# 作者模型
class Author(db.Model):# 表名__tablename__ = 'authors'# 字段名id = db.Column(db.Integer,primary_key=True) #作者idname = db.Column(db.String(16),unique=True) #作者名name# 关系引用# books是给Author自己用的,author是给Book模型用的books = db.relationship('Book',backref='author')def __refr__(self):return 'Author: %s ' % self.name# 书籍模型
class Book(db.Model):# 表名__tablename__ = 'books'# 字段名id = db.Column(db.Integer, primary_key=True)  # 书籍的idname = db.Column(db.String(16), unique=True)  # 书籍名nameauthor_id = db.Column(db.Integer,db.ForeignKey('authors.id'))def __refr__(self):return 'Book: %s %s ' % self.name,self.author_id# 自定义表单类
class AuthorForm(FlaskForm):author = StringField('作者',validators=[DataRequired()])book = StringField('书籍',validators=[DataRequired()])submit = SubmitField('提交')@app.route('/delete_author/<author_id>')
def delete_author(author_id):# 查询数据库，是否有该ID的作者，如果有就删除（先删书，再删作者），没有就提示错误# 1.查询数据库，author = Author.query.get(author_id)# 2.如果有就删除（先删书，再删作者）if author:try:# 查询之后直接删除Book.query.filter_by(author_id = author_id).delete()# 删除作者db.session.delete(author)db.session.commit()except Exception as e:print(e)flash('删除书籍出错！！！')db.session.rollback()# 3.没有就提示错误else:flash('作者找不到~')return redirect(url_for('index'))@app.route('/delete_book/<book_id>')
def delete_book(book_id):# 1. 查询数据库，是否有该ID的书，book = Book.query.get(book_id)# 2.如果有就删除，if book:try:db.session.delete(book)db.session.commit()except Exception as e:print(e)flash('删除书籍出错！！！')db.session.rollback()# 3.没有就提示错误else:flash('书籍找不到~')# 如何返回当前网址——》重定向# return redirect('www.baidu.com')# redirect():重定向，需要传入网址/路由地址# url_for():需要传入视图函数名，返回该视图函数对应的路由地址print(url_for('index'))return redirect(url_for('index'))@app.route('/',methods=['GET','POST'])
def index():# 创建自定义的表单类author_form = AuthorForm()'''验证逻辑:1. 调用WTF的函数实现验证2. 验证通过获取数据3. 判断作者是否存在4. 如果作者存在，判断书籍是否存在，没有重复书籍就添加书籍信息；如果重复就提示错误5. 如果作者不存在，添加作者和书籍6. 验证不通过就提示错误'''# 1. 调用WTF的函数实现验证if author_form.validate_on_submit():# 2. 验证通过获取数据author_name =  author_form.author.databook_name = author_form.book.data# 3. 判断作者是否存在:到数据库中查询author = Author.query.filter_by(name = author_name).first()# 4. 如果作者存在，if author:# 判断书籍是否存在，book = Book.query.filter_by(name = book_name).first()# 如果重复就提示错误if book:flash('已存在同名书籍！')# 没有重复书籍就添加书籍信息；else:try:new_book = Book(name = book_name,author_id=author.id)db.session.add(new_book)db.session.commit()except Exception as e:print(e)flash('添加书籍失败！')db.session.rollback() # 添加失败要进行回滚操作！# 5. 如果作者不存在,添加作者和书籍else:try:new_author = Author(name = author_name)db.session.add(new_author)db.session.commit()new_book = Book(name = book_name,author_id = new_author.id)db.session.add(new_book)db.session.commit()except Exception as e:print(e)flash('添加作者和书籍失败！')db.session.rollback()else:# 6. 验证不通过就提示错误if request.method == 'POST':flash('参数不全')# {查询所有的作者信息，让信息传递给模板 }authors = Author.query.all()return render_template('books.html',authors= authors,form = author_form)if __name__ == '__main__':db.drop_all()db.create_all()# 生成数据au1 = Author(name='老王')au2 = Author(name='老尹')au3 = Author(name='老刘')# 把数据提交给用户会话db.session.add_all([au1, au2, au3])# 提交会话db.session.commit()bk1 = Book(name='老王回忆录', author_id=au1.id)bk2 = Book(name='我读书少，你别骗我', author_id=au1.id)bk3 = Book(name='如何才能让自己更骚', author_id=au2.id)bk4 = Book(name='怎样征服美丽少女', author_id=au3.id)bk5 = Book(name='如何征服英俊少男', author_id=au3.id)# 把数据提交给用户会话db.session.add_all([bk1, bk2, bk3, bk4, bk5])# 提交会话db.session.commit()app.run(debug=True)

books.html文件

<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>图书管理</title>
</head>
<body><form method="post">{{ form.csrf_token() }}{{ form.author.label }} {{ form.author }} <br>{{ form.book.label }} {{ form.book }} <br>{{ form.submit }} <br></form><!--    显示消息闪现的内容-->{% for message in get_flashed_messages() %}{{message}}{% endfor %}<hr><!--    先遍历作者，然后在作者里遍历书籍--><ul>{% for author in authors %}<li>{{author.name}} <a href="{{url_for('delete_author', author_id = author.id)}}">删除</a></li><ul>{% for book in author.books %}<li>{{book.name}} <a href="{{url_for('delete_book', book_id = book.id)}}">删除</a></li>{% else %}<li>无</li>{% endfor %}</ul>{% endfor %}</ul></body>
</html>

第一种删除书籍的实现方法(通过post请求来实现)

myCode

from flask import Flask,render_template,request,redirect,url_for,jsonify
from flask_sqlalchemy import SQLAlchemy
from flask_wtf import FlaskForm
from wtforms import StringField,SubmitField
from wtforms.validators import DataRequired
import json
app = Flask(__name__)class Config(object):'''配置参数'''# 数据库sqlAlchemy的配置参数,数据库链接地址SQLALCHEMY_DATABASE_URI = "mysql://root:root@127.0.0.1:3306/author_book_py04"# 动态追踪修改设置，如未设置只会提示警告SQLALCHEMY_TRACK_MODIFICATIONS = TrueSECRET_KEY = "JDIOGDKFNKXNCV12345D4FSDFS"app.config.from_object(Config)db = SQLAlchemy(app)# 定义数据库的模型
class Author(db.Model):'''作者表'''__tablename__ = "tbl_authors"id = db.Column(db.Integer,primary_key=True)name = db.Column(db.String(32),unique=True)books = db.relationship("Book",backref = "author")class Book(db.Model):'''作者表'''__tablename__ = "tbl_books"id = db.Column(db.Integer,primary_key=True)name = db.Column(db.String(64),unique=True)author_id = db.Column(db.Integer,db.ForeignKey('tbl_authors.id'))# 创建表单模型类
class AuthorBookForm(FlaskForm):'''作者书籍表单模型类'''author_name = StringField(label="作者：",validators=[DataRequired("作者必填！")])book_name = StringField(label="书名：",validators=[DataRequired("书名必填！")])submit = SubmitField(label="保存")@app.route("/index",methods=["GET","POST"])
def index():# 创建表单对象form = AuthorBookForm()# 验证表单成功if form.validate_on_submit():author_name = form.author_name.databook_name = form.book_name.data# 保存到数据库author = Author(name=author_name)db.session.add(author)db.session.commit()book = Book(name=book_name,author_id=author.id)# book = Book(name=book_name,author=author)db.session.add(book)db.session.commit()# 查询数据库author_li = Author.query.all()return render_template("author_book.html",authors = author_li,form=form)# 约定前端传过来的数据格式：
# post  /delete_book  json
# {"book_id":xxx}# 删除书籍
@app.route("/delete_book",methods=["POST"])
def delete_book():# 提取参数# 如果前端发送的请求体数据是json格式，# get_json会解析成字典格式# 前提：要求前端传送的数据的# Content-Type:application/jsonreq_dict = request.get_json()# 将json格式字符串转换为python中的字典# json.loads(req_data)book_id = req_dict.get("book_id")# 删除数据book = Book.query.get(book_id)db.session.delete(book)db.session.commit()# "Content-Typel":"application/json"return jsonify(code=0,message="OK")if __name__ == '__main__':db.drop_all()db.create_all()# 生成数据au_xi = Author(name='我吃西红柿')au_qian = Author(name='萧潜')au_san = Author(name='唐家三少')db.session.add_all([au_xi,au_qian,au_san])db.session.commit()bk_xi = Book(name='吞噬星空',author_id=au_xi.id)bk_xi2 = Book(name='寸芒',author_id=au_qian.id)bk_qian = Book(name='飘渺之旅',author_id=au_qian.id)bk_san = Book(name='冰火魔厨',author_id=au_san.id)db.session.add_all([bk_xi,bk_xi2,bk_qian,bk_san])db.session.commit()app.run(debug=True)

<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>Title</title>
</head>
<body><form method="post">{{form.csrf_token}}{{form.author_name.label}}<p>{{form.author_name}}</p>{% for msg in form.author_name.errors %}<p>{{msg}}</p>{% endfor %}{{form.book_name.label}}<p>{{form.book_name}}</p>{% for msg in form.book_name.errors %}<p>{{msg}}</p>{% endfor %}{{form.submit}}</form><hr><ul>{% for author in authors %}<li>作者：{{author.name}}</li><ul>{% for book in author.books %}<li>书籍：{{book.name}}</li><a href="javascript:;"  book-id="{{book.id}}">删除</a>{% endfor %}</ul>{% endfor %}</ul><script src="../static/js/jquery-3.5.0.js"></script><script>$("a").click(function () {var data = {book_id:$(this).attr("book-id")};// # 将上面data字典格式的数据转换为json字符串格式var req_json = JSON.stringify(data)// $.post("/delete_book",req_json,function (resp) {//     if (resp.code ==0) {//         location.href = "/index";//     }// },"json")$.ajax({url:"/delete_book", //请求的后端urltype:"post", //请求方式data:req_json, // 向后端发送的请求体数据contentType:"application/json", //指明向后端发送的数据格式dataType:"json", // 指明后端返回的数据格式为jsonsuccess:function (resp) {if (resp.code == 0) {alert("ok")location.href = "/index";}}})})</script>
</body>
</html>

在这里插入图片描述
重点解读：

第二种删除书籍的实现方法(通过get请求来实现)

myCode

from flask import Flask,render_template,request,redirect,url_for,jsonify
from flask_sqlalchemy import SQLAlchemy
from flask_wtf import FlaskForm
from wtforms import StringField,SubmitField
from wtforms.validators import DataRequired
import json
app = Flask(__name__)class Config(object):'''配置参数'''# 数据库sqlAlchemy的配置参数,数据库链接地址SQLALCHEMY_DATABASE_URI = "mysql://root:root@127.0.0.1:3306/author_book_py04"# 动态追踪修改设置，如未设置只会提示警告SQLALCHEMY_TRACK_MODIFICATIONS = TrueSECRET_KEY = "JDIOGDKFNKXNCV12345D4FSDFS"app.config.from_object(Config)db = SQLAlchemy(app)# 定义数据库的模型
class Author(db.Model):'''作者表'''__tablename__ = "tbl_authors"id = db.Column(db.Integer,primary_key=True)name = db.Column(db.String(32),unique=True)books = db.relationship("Book",backref = "author")class Book(db.Model):'''作者表'''__tablename__ = "tbl_books"id = db.Column(db.Integer,primary_key=True)name = db.Column(db.String(64),unique=True)author_id = db.Column(db.Integer,db.ForeignKey('tbl_authors.id'))# 创建表单模型类
class AuthorBookForm(FlaskForm):'''作者书籍表单模型类'''author_name = StringField(label="作者：",validators=[DataRequired("作者必填！")])book_name = StringField(label="书名：",validators=[DataRequired("书名必填！")])submit = SubmitField(label="保存")@app.route("/index",methods=["GET","POST"])
def index():# 创建表单对象form = AuthorBookForm()# 验证表单成功if form.validate_on_submit():author_name = form.author_name.databook_name = form.book_name.data# 保存到数据库author = Author(name=author_name)db.session.add(author)db.session.commit()book = Book(name=book_name,author_id=author.id)# book = Book(name=book_name,author=author)db.session.add(book)db.session.commit()# 查询数据库author_li = Author.query.all()return render_template("author_book.html",authors = author_li,form=form)# 约定前端传过来的数据格式：
# post  /delete_book  json
# {"book_id":xxx}# # 删除书籍
# @app.route("/delete_book",methods=["POST"])
# def delete_book():
#     # 提取参数
#     # 如果前端发送的请求体数据是json格式，
#     # get_json会解析成字典格式
#     # 前提：要求前端传送的数据的
#     # Content-Type:application/json
#     req_dict = request.get_json()
#     # 将json格式字符串转换为python中的字典
#     # json.loads(req_data)
#
#     book_id = req_dict.get("book_id")
#
#     # 删除数据
#     book = Book.query.get(book_id)
#     db.session.delete(book)
#     db.session.commit()
#
#     # "Content-Typel":"application/json"
#     return jsonify(code=0,message="OK")
## 删除书籍
@app.route("/delete_book",methods=["GET"])
def delete_book():book_id = request.args.get("book_id")# 删除数据book = Book.query.get(book_id)db.session.delete(book)db.session.commit()return redirect(url_for("index"))if __name__ == '__main__':db.drop_all()db.create_all()# 生成数据au_xi = Author(name='我吃西红柿')au_qian = Author(name='萧潜')au_san = Author(name='唐家三少')db.session.add_all([au_xi,au_qian,au_san])db.session.commit()bk_xi = Book(name='吞噬星空',author_id=au_xi.id)bk_xi2 = Book(name='寸芒',author_id=au_qian.id)bk_qian = Book(name='飘渺之旅',author_id=au_qian.id)bk_san = Book(name='冰火魔厨',author_id=au_san.id)db.session.add_all([bk_xi,bk_xi2,bk_qian,bk_san])db.session.commit()app.run(debug=True)

<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>Title</title>
</head>
<body><form method="post">{{form.csrf_token}}{{form.author_name.label}}<p>{{form.author_name}}</p>{% for msg in form.author_name.errors %}<p>{{msg}}</p>{% endfor %}{{form.book_name.label}}<p>{{form.book_name}}</p>{% for msg in form.book_name.errors %}<p>{{msg}}</p>{% endfor %}{{form.submit}}</form><hr><ul>{% for author in authors %}<li>作者：{{author.name}}</li><ul>{% for book in author.books %}<li>书籍：{{book.name}}</li>
<!--            <a href="javascript:;"  book-id="{{book.id}}">删除</a>--><a href="/delete_book?book_id={{book.id}}" >GET删除</a>{% endfor %}</ul>{% endfor %}</ul><script src="../static/js/jquery-3.5.0.js"></script><script>// $("a").click(function () {//     var data = {//         book_id:$(this).attr("book-id")//     };//     // # 将上面data字典格式的数据转换为json字符串格式//     var req_json = JSON.stringify(data)////     // $.post("/delete_book",req_json,function (resp) {//     //     if (resp.code ==0) {//     //         location.href = "/index";//     //     }//     // },"json")//     $.ajax({//         url:"/delete_book", //请求的后端url//         type:"post", //请求方式//         data:req_json, // 向后端发送的请求体数据//         contentType:"application/json", //指明向后端发送的数据格式//         dataType:"json", // 指明后端返回的数据格式为json//         success:function (resp) {//             if (resp.code == 0) {//                 alert("ok")//                 location.href = "/index";//             }//         }//     })// })</script>
</body>
</html>