使用python streamlit库快速创建一个购物网站

streamlit

Streamlit 是一个基于 Python 的 Web 应用程序框架，致力于以更高效、更灵活的方式可视化数据，并分析结果。

Streamlit是一个开源库，可以帮助数据科学家和学者在短时间内开发机器学习 (ML) 可视化仪表板。只需几行代码，我们就可以构建并部署强大的数据应用程序。

功能设计

商品展示
商品选购
加入购物车
购物车结算
增加新商品
文件保存商品信息

函数/Page 设计

函数名	说明
load_products()	打开或创建存储商品信息的文件，并读取信息
save_products(products)	将商品信息保存在文件中
show_products()	用按钮显示所有商品信息
Select Product	读取商品名和数量，传给购物车
Shopping Cart	展示所有已选购商品，计算总价
Checkout	计算总价，点击买单后清空购物车
Add New Product	读取新商品信息，加入商品信息列表，写入文件，重新加载文件

源码

import streamlit as st
import json
import os

def load_products():
    if not os.path.exists('products.json'):
        with open('products.json', 'w') as file:
            file.write('{}')  # 创建一个空的 JSON 文件
    with open('products.json', 'r') as file:
        products = json.load(file)
    return products

def save_products(products):
    with open('products.json', 'w') as file:
        json.dump(products, file, indent=4)

# 初始化购物车
if 'shopping_cart' not in st.session_state:
    st.session_state.shopping_cart = []

# 初始化商品信息
if 'products' not in st.session_state:
    st.session_state.products = load_products()

def show_products():
    st.write("Current Products:")
    products = st.session_state.products
    product_names = list(products.keys())
    num_products = len(product_names)

    # 创建五列
    col1, col2, col3, col4, col5 = st.columns(5)

    # 在每列中显示产品信息
    for i in range(num_products):
        if i % 5 == 0:
            if col1.button(f"{product_names[i]} - ${products[product_names[i]]['price']} - {products[product_names[i]]['description']}"):
                st.session_state.shopping_cart.append((product_names[i], 1))
        elif i % 5 == 1:
            if col2.button(f"{product_names[i]} - ${products[product_names[i]]['price']} - {products[product_names[i]]['description']}"):
                st.session_state.shopping_cart.append((product_names[i], 1))
        elif i % 5 == 2:
            if col3.button(f"{product_names[i]} - ${products[product_names[i]]['price']} - {products[product_names[i]]['description']}"):
                st.session_state.shopping_cart.append((product_names[i], 1))
        elif i % 5 == 3:
            if col4.button(f"{product_names[i]} - ${products[product_names[i]]['price']} - {products[product_names[i]]['description']}"):
                st.session_state.shopping_cart.append((product_names[i], 1))
        else:
            if col5.button(f"{product_names[i]} - ${products[product_names[i]]['price']} - {products[product_names[i]]['description']}"):
                st.session_state.shopping_cart.append((product_names[i], 1))

def main():
    st.title('Welcome to the Convenience Store')
    page = st.sidebar.radio("Page", ["Select Product", "Shopping Cart", "Checkout", "Add New Product"])

    if page == "Select Product":
        show_products()
        selected_product = st.selectbox('Select a product', list(st.session_state.products.keys()), format_func=lambda x: f"{x} - ${st.session_state.products[x]['price']} - {st.session_state.products[x]['description']}")
        quantity = st.number_input('Quantity', min_value=1, max_value=10)
        if st.button('Add to cart'):
            st.session_state.shopping_cart.append((selected_product, quantity))
            st.success('Added to cart!')
            st.experimental_rerun()  # 刷新页面，更新商品信息

    elif page == "Shopping Cart":
        st.title('Shopping Cart')
        for item in st.session_state.shopping_cart:
            st.write(f"{item[0]} - Quantity: {item[1]}")
        total_cost = sum([st.session_state.products[item[0]]['price'] * item[1] for item in st.session_state.shopping_cart])
        st.write(f"Total Cost: ${total_cost}")

    elif page == "Checkout":
        st.title('Checkout')
        total_cost = sum([st.session_state.products[item[0]]['price'] * item[1] for item in st.session_state.shopping_cart])
        st.write(f"Total Cost: ${total_cost}")
        if st.button('Confirm Purchase'):
            st.success('Thank you for your purchase!')
            st.session_state.shopping_cart = []

    elif page == "Add New Product":
        st.title('Add New Product')
        new_product_name = st.text_input('Product name')
        new_product_price = st.number_input('Product price')
        new_product_description = st.text_input('Product description')
        if st.button('Add Product'):
            st.session_state.products[new_product_name] = {'price': new_product_price, 'description': new_product_description}
            save_products(st.session_state.products)  # 将新的商品信息保存到文件
            st.success('Product added successfully!')
            st.experimental_rerun()  # 刷新页面，显示新商品

if __name__ == "__main__":
    main()