代码实现点餐系统

点餐系统可以分为客户端和服务端两部分。客户端主要负责展示菜单、接收用户输入、显示订单等功能；服务端则负责处理客户端发送的请求，生成订单并将其保存到数据库中。

以下是一个简单的点餐系统的代码示例：

服务端代码：

import sqlite3

# 连接数据库
conn = sqlite3.connect('orders.db')
c = conn.cursor()

# 创建订单表
c.execute('''CREATE TABLE IF NOT EXISTS orders
             (id INTEGER PRIMARY KEY AUTOINCREMENT, 
             name TEXT, 
             phone TEXT, 
             address TEXT, 
             items TEXT)''')

# 处理客户端请求
def handle_request(request):
    if request['action'] == 'add_order':
        # 添加新订单
        name = request['name']
        phone = request['phone']
        address = request['address']
        items = request['items']
        c.execute('''INSERT INTO orders (name, phone, address, items)
                     VALUES (?, ?, ?, ?)''', (name, phone, address, items))
        conn.commit()
        return {'status': 'success'}
    elif request['action'] == 'get_orders':
        # 获取所有订单
        c.execute('SELECT * FROM orders')
        orders = c.fetchall()
        return {'status': 'success', 'orders': orders}
    else:
        return {'status': 'error', 'message': 'Invalid action'}

# 关闭数据库连接
conn.close()

客户端代码：

import requests

# 服务端地址
SERVER_URL = 'http://localhost:8000'

def show_menu(menu):
    # 展示菜单
    print('Menu:')
    for item in menu:
        print(f'{item["name"]}: {item["price"]}')

def get_order():
    # 获取用户订单
    items = []
    while True:
        item_name = input('Enter item name (or "done" to finish): ')
        if item_name == 'done':
            break
        quantity = int(input('Enter quantity: '))
        items.append({'name': item_name, 'quantity': quantity})
    return items

def place_order():
    # 下单
    name = input('Enter your name: ')
    phone = input('Enter your phone number: ')
    address = input('Enter your address: ')
    items = get_order()
    response = requests.post(f'{SERVER_URL}/order', json={
        'name': name,
        'phone': phone,
        'address': address,
        'items': items
    })
    if response.status_code == 200:
        print('Order placed successfully')
    else:
        print(f'Error placing order: {response.text}')

def view_orders():
    # 查看所有订单
    response = requests.get(f'{SERVER_URL}/orders')
    if response.status_code == 200:
        orders = response.json()['orders']
        for order in orders:
            print(f'{order[1]} ({order[2]}): {order[4]}')
    else:
        print(f'Error getting orders: {response.text}')

# 展示菜单
menu = [
    {'name': 'Pizza', 'price': 10},
    {'name': 'Burger', 'price': 5},
    {'name': 'Fries', 'price': 3},
    {'name': 'Coke', 'price': 2},
]
show_menu(menu)

# 处理用户输入
while True:
    action = input('Enter action (order/view/quit): ')
    if action == 'order':
        place_order()
    elif action == 'view':
        view_orders()
    elif action == 'quit':
        break
    else:
        print('Invalid action')

注意，这只是一个非常简单的示例，实际的点餐系统可能需要更多的功能和更复杂的代码。