用python语言编写一个物品租赁管理系统

好的，我可以为您提供一个Python语言编写的物品租赁管理系统的示例代码，以下是一个基本的模板：

import sqlite3
import datetime

conn = sqlite3.connect('items.db')
c = conn.cursor()

# 创建用户表
def create_user_table():
    c.execute('''CREATE TABLE IF NOT EXISTS user
                 (id INTEGER PRIMARY KEY AUTOINCREMENT,
                  username TEXT NOT NULL,
                  password TEXT NOT NULL)''')
    conn.commit()

# 创建物品表
def create_item_table():
    c.execute('''CREATE TABLE IF NOT EXISTS item
                 (id INTEGER PRIMARY KEY AUTOINCREMENT,
                  name TEXT NOT NULL,
                  description TEXT NOT NULL,
                  is_rented INTEGER)''')
    conn.commit()

# 创建租赁表
def create_rental_table():
    c.execute('''CREATE TABLE IF NOT EXISTS rental
                 (id INTEGER PRIMARY KEY AUTOINCREMENT,
                  item_id INTEGER NOT NULL,
                  user_id INTEGER NOT NULL,
                  rental_time TEXT NOT NULL,
                  return_time TEXT,
                  FOREIGN KEY (item_id) REFERENCES item(id),
                  FOREIGN KEY (user_id) REFERENCES user(id))''')
    conn.commit()

# 用户注册
def register():
    username = input('请输入用户名：')
    password = input('请输入密码：')
    c.execute("INSERT INTO user (username, password) VALUES (?, ?)", (username, password))
    conn.commit()
    print('注册成功！')

# 用户登录
def login():
    username = input('请输入用户名：')
    password = input('请输入密码：')
    c.execute("SELECT id FROM user WHERE username = ? AND password = ?", (username, password))
    user_id = c.fetchone()
    if user_id:
        print('登录成功！')
        return user_id[0]
    else:
        print('用户名或密码错误！')
        return None

# 添加物品
def add_item():
    name = input('请输入物品名称：')
    description = input('请输入物品描述：')
    c.execute("INSERT INTO item (name, description, is_rented) VALUES (?, ?, ?)", (name, description, 0))
    conn.commit()
    print('添加成功！')

# 查询物品
def query_item():
    name = input('请输入要查询的物品名称：')
    c.execute("SELECT id, name, description, is_rented FROM item WHERE name = ?", (name,))
    item = c.fetchone()
    if item:
        print('物品ID：', item[0])
        print('物品名称：', item[1])
        print('物品描述：', item[2])
        if item[3] == 0:
            print('可租借')
        else:
            print('已租借')
    else:
        print('未查询到该物品！')

# 租借物品
def rent_item(user_id):
    item_id = input('请输入要租借的物品ID：')
    c.execute("SELECT is_rented FROM item WHERE id = ?", (item_id,))
    is_rented = c.fetchone()
    if is_rented and is_rented[0] == 0:
        rental_time = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')
        c.execute("UPDATE item SET is_rented = 1 WHERE id = ?", (item_id,))
        c.execute("INSERT INTO rental (item_id, user_id, rental_time) VALUES (?, ?, ?)", (item_id, user_id, rental_time))
        conn.commit()
        print('租借成功！')
    else:
        print('该物品已被租借或不存在！')

# 归还物品
def return_item():
    rental_id = input('请输入租赁记录ID：')
    return_time = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')
    c.execute("UPDATE rental SET return_time = ? WHERE id = ?", (return_time, rental_id))
    c.execute("SELECT item_id FROM rental WHERE id = ?", (rental_id,))
    item_id = c.fetchone()
    if item_id:
        c.execute("UPDATE item SET is_rented = 0 WHERE id = ?", (item_id[0],))
        conn.commit()
        print('归还成功！')
    else:
        print('未查询到该租赁记录！')

# 程序入口
if __name__ == '__main__':
    create_user_table()
    create_item_table()
    create_rental_table()
    while True:
        print('1. 注册')
        print('2. 登录')
        print('3. 添加物品')
        print('4. 查询物品')
        print('5. 租借物品')
        print('6. 归还物品')
        print('7. 退出')
        choice = input('请输入操作编号：')
        if choice == '1':
            register()
        elif choice == '2':
            user_id = login()
            if user_id:
                while True:
                    print('1. 添加物品')
                    print('2. 查询物品')
                    print('3. 租借物品')
                    print('4. 归还物品')
                    print('5. 返回上级菜单')
                    choice = input('请输入操作编号：')
                    if choice == '1':
                        add_item()
                    elif choice == '2':
                        query_item()
                    elif choice == '3':
                        rent_item(user_id)
                    elif choice == '4':
                        return_item()
                    elif choice == '5':
                        break
        elif choice == '3':
            add_item()
        elif choice == '4':
            query_item()
        elif choice == '5':
            print('请先登录！')
        elif choice == '6':
            print('请先登录！')
        elif choice == '7':
            break
        else:
            print('无效操作，请重新输入！')
    conn.close()

以上代码仅供参考，具体的实现需要根据您的需求进行修改和完善。