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在查询和添加数据的基础上,本文将详细介绍如何实现数据的修改和删除功能。我们将继续使用之前的update_and_delete.py
文件,该文件已经包含了查询和添加数据的功能。文件结构如下:
我们继续使用之前创建的数据表和数据模型。数据库结构如前所述,Phone
模型和Person
模型之间有关系,一个Person
可以拥有多个Phone
。以下是update_and_delete.py
的完整代码:
from flask import Flask, render_template, request, redirect, flashfrom flask_sqlalchemy import SQLAlchemyimport randomapp = Flask(__name__)app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://admin:Mysql!123@127.0.0.1:3306/MyDB_one'app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = Trueapp.config['SQLALCHEMY_ECHO'] = Trueapp.config['SECRET_KEY'] = 'NFAIOSDFHASOGHAOSPIGAOWE'db = SQLAlchemy(app)class Phone(db.Model): __tablename__ = 'Phone_tb' pid = db.Column(db.Integer, primary_key=True) name = db.Column(db.String(32)) person_id = db.Column(db.Integer, db.ForeignKey('Person_tb.mid')) def __repr__(self): return 'Phone_name: {}'.format(self.name)class Person(db.Model): __tablename__ = 'Person_tb' mid = db.Column(db.Integer, primary_key=True) name = db.Column(db.String(64), unique=True) age = db.Column(db.Integer) phones = db.relationship('Phone', backref='person', lazy='dynamic') def __repr__(self): return 'Person_name: {}'.format(self.name)@app.route('/', methods=['GET', 'POST'])def index(): if request.method == 'GET': persons = Person.query.all() return render_template('update_and_delete.html', persons=persons) if request.method == 'POST': person_name = request.form.get('person') if not person_name: return redirect('/') submit = request.form.get('search') if submit == '查询': persons = Person.query.filter_by(name=person_name) return render_template('update_and_delete.html', persons=persons) submit = request.form.get('add') if submit == '添加': phone_name = request.form.get('phone') person = Person.query.filter_by(name=person_name).first() if person: if not phone_name: return redirect('/') phone = Phone.query.filter(Phone.name == phone_name, Phone.person_id == person.mid).first() if phone: flash('数据已存在!') else: phone = Phone(name=phone_name, person_id=person.mid) add_data(phone) else: person = Person(name=person_name, age=random.randint(18, 25)) add_data(person) if not phone_name: return redirect('/') phone = Phone(name=phone_name) phone.person = person add_data(phone) return redirect('/')def add_data(obj): try: db.session.add(obj) db.session.commit() except Exception as e: print(e) db.session.rollback() flash("添加失败")if __name__ == '__main__': app.run(debug=True)
创建templates/update_and_delete.html
文件,内容如下:
{% for message in get_flashed_messages() %} {{ message }} {% endfor %}Person Manage
添加新的路由update_person/<id>
来处理人名修改:
@app.route("/update_person/", methods=['GET', 'POST'])def update_person(id): person_name = request.form.get('person_{}'.format(id)) if not person_name: flash("请输入修改后的人名") return redirect('/') person = Person.query.get(id) if not person: flash("此人不存在") return redirect('/') try: person.name = person_name db.session.merge(person) db.session.commit() except Exception as e: print(e) db.session.rollback() return redirect('/')
访问http://localhost:5000
,选择一个Person
,输入需要修改的人名并点击Modify
,即可完成修改。
添加新的路由update_phone/<id>
来处理手机修改:
@app.route("/update_phone/", methods=['GET', 'POST'])def update_phone(id): phone_name = request.form.get('phone_{}'.format(id)) if not phone_name: flash("请输入修改后的手机") return redirect('/') phone = Phone.query.get(id) if not phone: flash("此手机不存在") return redirect('/') try: phone.name = phone_name db.session.merge(phone) db.session.commit() except Exception as e: print(e) db.session.rollback() return redirect('/')
访问http://localhost:5000
,选择一个Phone
,输入需要修改的手机名并点击Modify
,即可完成修改。
添加新的路由delete_person/<id>
来处理人名删除:
@app.route("/delete_person/")def delete_person(id): person = Person.query.get(id) if not person: flash("此人不存在") return redirect('/') try: Phone.query.filter(Phone.person_id == person.mid).delete() db.session.delete(person) db.session.commit() except Exception as e: print(e) db.session.rollback() return redirect('/')
访问http://localhost:5000
,选择一个Person
,点击Delete
,确认后即可删除该人及其关联的手机。
添加新的路由delete_phone/<id>
来处理手机删除:
@app.route("/delete_phone/")def delete_phone(id): phone = Phone.query.get(id) if not phone: flash("此手机不存在") return redirect('/') try: db.session.delete(phone) db.session.commit() except Exception as e: print(e) db.session.rollback() return redirect('/')
访问http://localhost:5000
,选择一个Phone
,点击Delete
,确认后即可删除该手机。
以上代码实现了所有数据的增删改查功能,能够满足基本的数据管理需求。请根据实际需求扩展功能或调整逻辑。
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