python高级4

练习：

使用已学习的所有知识，加上文件等操作，实现一个名片管理系统。具体功能要是实现（菜单）： **************名片管理系统************* 1.增加一个名片 2.删除一个名片 3.修改一个名片 4.查找一个名片 5.显示所有名片 ******************************************* 【一个名片里的信息有：姓名、联系方式、QQ、住址】

import json
import os


class CardManager:
    FILE_PATH = "cards.json"

    def __init__(self):
        """初始化：如果文件不存在，则创建一个空 JSON 文件"""
        if not os.path.exists(self.FILE_PATH):
            with open(self.FILE_PATH, "w", encoding="utf-8") as f:
                json.dump([], f, ensure_ascii=False)

    def load_data(self):
        """读取 JSON 文件数据"""
        with open(self.FILE_PATH, "r", encoding="utf-8") as f:
            return json.load(f)

    def save_data(self, data):
        """保存数据到 JSON 文件"""
        with open(self.FILE_PATH, "w", encoding="utf-8") as f:
            json.dump(data, f, ensure_ascii=False, indent=4)

    def add_card(self, name, phone, qq, address):
        """添加名片"""
        data = self.load_data()
        card = {"name": name, "phone": phone, "qq": qq, "address": address}
        data.append(card)
        self.save_data(data)
        print(f"名片添加成功：{card}")

    def delete_card(self, name):
        """删除名片"""
        data = self.load_data()
        new_data = [card for card in data if card["name"] != name]
        if len(new_data) == len(data):
            print(f"未找到名片：{name}")
        else:
            self.save_data(new_data)
            print(f"名片已删除：{name}")

    def update_card(self, name, phone=None, qq=None, address=None):
        """修改名片"""
        data = self.load_data()
        for card in data:
            if card["name"] == name:
                if phone:
                    card["phone"] = phone
                if qq:
                    card["qq"] = qq
                if address:
                    card["address"] = address
                self.save_data(data)
                print(f"名片已更新：{card}")
                return
        print(f"未找到名片：{name}")

    def search_card(self, name):
        """查找名片"""
        data = self.load_data()
        results = [card for card in data if name in card["name"]]
        if results:
            print("查询结果：")
            for card in results:
                print(card)
        else:
            print(f"没有找到名片：{name}")

    def show_all(self):
        """显示所有名片"""
        data = self.load_data()
        if data:
            print("名片列表：")
            for card in data:
                print(card)
        else:
            print("没有任何名片信息")


# ========== 主菜单 ==========
def main():
    manager = CardManager()

    while True:
        print("\n************** 名片管理系统 **************")
        print("1. 增加一个名片")
        print("2. 删除一个名片")
        print("3. 修改一个名片")
        print("4. 查找一个名片")
        print("5. 显示所有名片")
        print("0. 退出系统")
        print("*******************************************")

        choice = input("请选择操作（0-5）：")

        if choice == "1":
            name = input("请输入姓名：")
            phone = input("请输入联系方式：")
            qq = input("请输入 QQ 号码：")
            address = input("请输入住址：")
            manager.add_card(name, phone, qq, address)

        elif choice == "2":
            name = input("请输入要删除的名片姓名：")
            manager.delete_card(name)

        elif choice == "3":
            name = input("请输入要修改的名片姓名：")
            phone = input("新联系方式（按回车跳过）：") or None
            qq = input("新 QQ（按回车跳过）：") or None
            address = input("新住址（按回车跳过）：") or None
            manager.update_card(name, phone, qq, address)

        elif choice == "4":
            name = input("请输入要查找的名片姓名：")
            manager.search_card(name)

        elif choice == "5":
            manager.show_all()

        elif choice == "0":
            print("退出系统")
            break

        else:
            print("请输入正确的选项！")


# 运行程序
if __name__ == "__main__":
    main()

 cards.json：

[
    {
        "name": "张三",
        "phone": "10001",
        "qq": "10002",
        "address": "10003"
    }
]